diff --git a/java/src/org/broadinstitute/sting/playground/gatk/walkers/Recalibration/Covariate.java b/java/src/org/broadinstitute/sting/playground/gatk/walkers/Recalibration/Covariate.java
index d48f389a9..e107aca84 100644
--- a/java/src/org/broadinstitute/sting/playground/gatk/walkers/Recalibration/Covariate.java
+++ b/java/src/org/broadinstitute/sting/playground/gatk/walkers/Recalibration/Covariate.java
@@ -2,12 +2,41 @@ package org.broadinstitute.sting.playground.gatk.walkers.Recalibration;
 
 import net.sf.samtools.SAMRecord;
 
+/*
+ * Copyright (c) 2009 The Broad Institute
+ *
+ * Permission is hereby granted, free of charge, to any person
+ * obtaining a copy of this software and associated documentation
+ * files (the "Software"), to deal in the Software without
+ * restriction, including without limitation the rights to use,
+ * copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following
+ * conditions:
+ *
+ * The above copyright notice and this permission notice shall be
+ * included in all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
+ * OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
+ * HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
+ * WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
+ * OTHER DEALINGS IN THE SOFTWARE.
+ */
+
 /**
  * Created by IntelliJ IDEA.
  * User: rpoplin
  * Date: Oct 30, 2009
+ *
+ * The Covariate interface. A Covariate is a feature used in the recalibration that can be picked out of the read and corresponding reference bases 
  */
+
 public interface Covariate {
-	public Comparable<?> getValue(SAMRecord read, int offset, char[] refBases); // used to pick out the value from the read and etc
-	public Comparable<?> getValue(String str); // used to get value from input file
+	public Comparable getValue(SAMRecord read, int offset, char[] refBases); // used to pick out the value from the read and reference bases
+	public Comparable getValue(String str); // used to get value from input file
+    public int estimatedNumberOfBins(); // used to estimate the amount space required in the hashmap
 }
diff --git a/java/src/org/broadinstitute/sting/playground/gatk/walkers/Recalibration/CovariateCounterWalker.java b/java/src/org/broadinstitute/sting/playground/gatk/walkers/Recalibration/CovariateCounterWalker.java
index 36ad4b0b1..1ec584ebf 100755
--- a/java/src/org/broadinstitute/sting/playground/gatk/walkers/Recalibration/CovariateCounterWalker.java
+++ b/java/src/org/broadinstitute/sting/playground/gatk/walkers/Recalibration/CovariateCounterWalker.java
@@ -16,10 +16,47 @@ import java.util.*;
 
 import net.sf.samtools.SAMRecord;
 
+/*
+ * Copyright (c) 2009 The Broad Institute
+ *
+ * Permission is hereby granted, free of charge, to any person
+ * obtaining a copy of this software and associated documentation
+ * files (the "Software"), to deal in the Software without
+ * restriction, including without limitation the rights to use,
+ * copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following
+ * conditions:
+ *
+ * The above copyright notice and this permission notice shall be
+ * included in all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
+ * OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
+ * HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
+ * WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
+ * OTHER DEALINGS IN THE SOFTWARE.
+ */
+
 /**
  * Created by IntelliJ IDEA.
  * User: rpoplin
  * Date: Nov 3, 2009
+ *
+ * This walker is designed to work as the first pass in a two-pass processing step.
+ * It does a by-locus traversal operating only at sites that are not in dbSNP.
+ * We assume that all mismatches we see are therefore errors.
+ * This walker generates tables based on various user-specified covariates (such as read group, reported quality score, cycle, and dinuc)
+ * Since there is a large amount of data one can then calculate an empirical probability of error
+ *   given the particular covariates seen at this site, where p(error) = num mismatches / num observations
+ * The output file is a CSV list of (several covariate values, num observations, num mismatches, empirical quality score)
+ * The first lines of the output file give the name of the covariate classes that were used for this calculation.
+ *
+ * Note: ReadGroupCovariate and QualityScoreCovariate are required covariates and are automatically added first.
+ * Note: This walker is designed to be used in conjunction with TableRecalibrationWalker.
  */
 
 @WalkerName("CountCovariatesRefactored")
@@ -36,15 +73,18 @@ public class CovariateCounterWalker extends LocusWalker<Integer, PrintStream> {
     @Argument(fullName="recal_file", shortName="rf", required=false, doc="Filename for the outputted covariates table recalibration file")
     public String RECAL_FILE = "output.recal_data.csv";
 
-    protected static RecalDataManager dataManager;
-    protected static ArrayList<Covariate> requestedCovariates;
+    protected static RecalDataManager dataManager; // Holds the data HashMap, mostly used by TableRecalibrationWalker to create collapsed data hashmaps
+    protected static ArrayList<Covariate> requestedCovariates; // A list to hold the covariate objects that were requested
 
+    /**
+     * Parse the -cov arguments and create a list of covariates to be used here
+     * Based on the covariates' estimates for initial capacity allocate the data hashmap
+     */
     public void initialize() {
 
-        dataManager = new RecalDataManager();
-
         // Get a list of all available covariates
         List<Class<? extends Covariate>> classes = PackageUtils.getClassesImplementingInterface(Covariate.class);
+        int estimatedCapacity = 1; // start at one because capacity is multiplicative for each covariate
 
         // Print and exit if that's what was requested
         if ( LIST_ONLY ) {
@@ -57,7 +97,7 @@ public class CovariateCounterWalker extends LocusWalker<Integer, PrintStream> {
             System.exit( 0 ); // early exit here because user requested it
         }
 
-        // Initialize the requested covariates
+        // Initialize the requested covariates by parsing the -cov argument
         requestedCovariates = new ArrayList<Covariate>();
         requestedCovariates.add( new ReadGroupCovariate() );    // Read Group Covariate is a required covariate for the recalibration calculation
         requestedCovariates.add( new QualityScoreCovariate() ); // Quality Score Covariate is a required covariate for the recalibration calculation
@@ -67,11 +107,13 @@ public class CovariateCounterWalker extends LocusWalker<Integer, PrintStream> {
                 boolean foundClass = false;
                 for( Class<?> covClass : classes ) {
 
-                    if( requestedCovariateString.equalsIgnoreCase( covClass.getSimpleName() ) ) {
+                    if( requestedCovariateString.equalsIgnoreCase( covClass.getSimpleName() ) ) { // -cov argument matches the class name for an implementing class
                         foundClass = true;
                         try {
                             Covariate covariate = (Covariate)covClass.newInstance();
                             requestedCovariates.add( covariate );
+                            estimatedCapacity *= covariate.estimatedNumberOfBins(); // update the estimated initial capacity
+                            
                             if (covariate instanceof ReadGroupCovariate || covariate instanceof QualityScoreCovariate) {
                                 throw new StingException( "ReadGroupCovariate and QualityScoreCovariate are required covariates and are therefore added for you. Please remove them from the -cov list" );
                             }
@@ -92,27 +134,48 @@ public class CovariateCounterWalker extends LocusWalker<Integer, PrintStream> {
 
         logger.info( "The covariates being used here: " );
         logger.info( requestedCovariates );
+
+        dataManager = new RecalDataManager( estimatedCapacity );
     }
-    
+
+
+    //---------------------------------------------------------------------------------------------------------------
+    //
+    // map
+    //
+    //---------------------------------------------------------------------------------------------------------------
+
+    /**
+     * For each read at this locus get the various covariate values and increment that location in the map based on
+     *   whether or not the base matches the reference at this particular location
+     * @param tracker the reference metadata tracker
+     * @param ref the reference context
+     * @param context the alignment context
+     * @return returns 1, but this value isn't used in the reduce step
+     */
     public Integer map( RefMetaDataTracker tracker, ReferenceContext ref, AlignmentContext context ) {
 
         rodDbSNP dbsnp = rodDbSNP.getFirstRealSNP(tracker.getTrackData("dbsnp", null));
+
         // Only use data from non-dbsnp sites
         // Assume every mismatch at a non-dbsnp site is indicitive of poor quality
         if( dbsnp == null ) {
             List<SAMRecord> reads = context.getReads();
             List<Integer> offsets = context.getOffsets();
-            SAMRecord read; // preallocate for use in for loop below
-            int offset; // preallocate for use in for loop below
+            SAMRecord read;
+            int offset;
+
+            // For each read at this locus
             for( int iii = 0; iii < reads.size(); iii++ ) {
                 read = reads.get(iii);
                 offset = offsets.get(iii);
 
-                // Only use data from reads with mapping quality above given quality value and base quality greater than zero
+                // Only use data from reads with mapping quality above specified quality value and base quality greater than zero
                 byte[] quals = read.getBaseQualities();
                 if( read.getMappingQuality() >= MIN_MAPPING_QUALITY && quals[offset] > 0)
-                {                    
-                    if( offset > 0 && offset < (read.getReadLength() - 1) ) { // skip first and last bases because they don't have a dinuc count
+                {
+                    // Skip first and last bases because they don't have a dinuc count
+                    if( offset > 0 && offset < (read.getReadLength() - 1) ) {
                         updateDataFromRead(read, offset, ref);
                     }
                 }
@@ -124,43 +187,69 @@ public class CovariateCounterWalker extends LocusWalker<Integer, PrintStream> {
         return 1;
     }
 
+    /**
+     * Major workhorse routine for this walker.
+     * Loop through the list of requested covariates and pick out the value from the read, offset, and reference
+     * Using the list of covariate values as a key, pick out the RecalDatum and increment,
+     *   adding one to the number of observations and potentially one to the number of mismatches
+     * @param read the read
+     * @param offset the offset in the read for this locus
+     * @param ref the reference context
+     */
     private void updateDataFromRead(SAMRecord read, int offset, ReferenceContext ref) {
 
-        List<Comparable<?>> key = new ArrayList<Comparable<?>>();
-        Comparable<?> keyElement; // preallocate for use in for loop below
+        List<Comparable> key = new ArrayList<Comparable>();
+        Comparable keyElement;
         boolean badKey = false;
+
+        // Loop through the list of requested covariates and pick out the value from the read, offset, and reference
         for( Covariate covariate : requestedCovariates ) {
             keyElement = covariate.getValue( read, offset, ref.getBases() );
             if( keyElement != null ) {
                 key.add( keyElement );
             } else {
-                badKey = true;
+                badKey = true; // covariate returned bad value, for example dinuc returns null because base = 'N'
             }
         }
 
+        // Using the list of covariate values as a key, pick out the RecalDatum
         RecalDatum datum = null;
         if( !badKey ) {
             datum = dataManager.data.get( key );
             if( datum == null ) { // key doesn't exist yet in the map so make a new bucket and add it
-                datum = new RecalDatum();
+                datum = new RecalDatum(); // initialized with zeros, will be incremented at end of method
                 dataManager.data.put( key, datum );
             }
         }
 
+        // Need the bases to determine whether or not we have a mismatch
         byte[] bases = read.getReadBases();
 
         char base = (char)bases[offset];
         char refBase = ref.getBase();
+        // Get the complement base strand if we are a negative direction read
         if ( read.getReadNegativeStrandFlag() ) {
             refBase = BaseUtils.simpleComplement( refBase );
             base = BaseUtils.simpleComplement( base );
         }
 
         if( datum != null ) {
+            // Add one to the number of observations and potentially one to the number of mismatches
             datum.increment( base, refBase );
         }
     }
-   
+
+
+    //---------------------------------------------------------------------------------------------------------------
+    //
+    // reduce
+    //
+    //---------------------------------------------------------------------------------------------------------------
+
+    /**
+     * Initialize the reudce step by creating a PrintStream from the filename specified as an argument to the walker.
+     * @return returns a PrintStream created from the -rf filename
+     */
     public PrintStream reduceInit() {
         try {
             return new PrintStream( RECAL_FILE );
@@ -169,10 +258,20 @@ public class CovariateCounterWalker extends LocusWalker<Integer, PrintStream> {
         }
     }
 
+    /**
+     * The Reduce method doesn't do anything for this walker.
+     * @param value result of the map.
+     * @param recalTableStream the PrintStream
+     * @return returns the PrintStream used to output the CSV data
+     */
     public PrintStream reduce( Integer value, PrintStream recalTableStream ) {
         return recalTableStream; // nothing to do here
     }
 
+    /**
+     * Write out the full data hashmap to disk in CSV format
+     * @param recalTableStream the PrintStream to write out to
+     */
     public void onTraversalDone( PrintStream recalTableStream ) {
         out.print( "Writing raw recalibration data..." );
         for( Covariate cov : requestedCovariates ) {
@@ -184,16 +283,19 @@ public class CovariateCounterWalker extends LocusWalker<Integer, PrintStream> {
         recalTableStream.close();
     }
 
+    /**
+     * For each entry (key-value pair) in the data hashmap output the Covariate's values as well as the RecalDatum's data in CSV format
+     * @param recalTableStream the PrintStream to write out to
+     */
     private void outputToCSV( PrintStream recalTableStream ) {
-        for( Map.Entry<List<? extends Comparable<?>>, RecalDatum> entry : dataManager.data.entrySet() ) {
-            //for( int iii = 0; iii < entry.getKey().size(); iii++ ) {
-                //index = Integer.parseInt( (entry.getKey().get( iii )).toString());
-                //recalTableStream.print( requestedCovariates.get( iii ).getValue( index ) + "," );
-            //	recalTableStream.print( entry.getKey().get(iii) )
-            //}
-        	for( Comparable<?> comp : entry.getKey() ) {
+        // For each entry in the data hashmap
+        for( Map.Entry<List<? extends Comparable>, RecalDatum> entry : dataManager.data.entrySet() ) {
+            // For each Covariate in the key
+            for( Comparable comp : entry.getKey() ) {
+                // Output the Covariate's value
         		recalTableStream.print( comp + "," );
         	}
+            // Output the RecalDatum entry
             recalTableStream.println( entry.getValue().outputToCSV() );
         }
     }
diff --git a/java/src/org/broadinstitute/sting/playground/gatk/walkers/Recalibration/CycleCovariate.java b/java/src/org/broadinstitute/sting/playground/gatk/walkers/Recalibration/CycleCovariate.java
index f6acbcdd3..e5d2d20a8 100755
--- a/java/src/org/broadinstitute/sting/playground/gatk/walkers/Recalibration/CycleCovariate.java
+++ b/java/src/org/broadinstitute/sting/playground/gatk/walkers/Recalibration/CycleCovariate.java
@@ -2,16 +2,42 @@ package org.broadinstitute.sting.playground.gatk.walkers.Recalibration;
 
 import net.sf.samtools.SAMRecord;
 
+/*
+ * Copyright (c) 2009 The Broad Institute
+ *
+ * Permission is hereby granted, free of charge, to any person
+ * obtaining a copy of this software and associated documentation
+ * files (the "Software"), to deal in the Software without
+ * restriction, including without limitation the rights to use,
+ * copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following
+ * conditions:
+ *
+ * The above copyright notice and this permission notice shall be
+ * included in all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
+ * OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
+ * HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
+ * WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
+ * OTHER DEALINGS IN THE SOFTWARE.
+ */
+
 /**
  * Created by IntelliJ IDEA.
  * User: rpoplin
  * Date: Oct 30, 2009
  */
+
 public class CycleCovariate implements Covariate {
 
     public String platform;
 
-    public CycleCovariate() { // empty constructor is required by CovariateCounterWalker
+    public CycleCovariate() { // empty constructor is required to instantiate covariate in CovariateCounterWalker and TableRecalibrationWalker
         platform = null;
     }
 
@@ -19,8 +45,8 @@ public class CycleCovariate implements Covariate {
         platform = _platform;
     }
 
-    public Comparable<?> getValue(SAMRecord read, int offset, char[] refBases) {
-        //BUGBUG: assumes Solexia platform
+    public Comparable getValue(SAMRecord read, int offset, char[] refBases) {
+        //BUGBUG: assumes Solexa platform
         Integer cycle = offset;
         if( read.getReadNegativeStrandFlag() ) {
             cycle = read.getReadLength() - (offset + 1);
@@ -28,10 +54,14 @@ public class CycleCovariate implements Covariate {
         return cycle;
     }
     
-    public Comparable<?> getValue(String str) {
+    public Comparable getValue(String str) {
         return Integer.parseInt( str );
     }
 
+    public int estimatedNumberOfBins() {
+        return 100;
+    }
+
     public String toString() {
         return "Cycle";
     }
diff --git a/java/src/org/broadinstitute/sting/playground/gatk/walkers/Recalibration/DinucCovariate.java b/java/src/org/broadinstitute/sting/playground/gatk/walkers/Recalibration/DinucCovariate.java
index 991a2cf35..2613a26a1 100755
--- a/java/src/org/broadinstitute/sting/playground/gatk/walkers/Recalibration/DinucCovariate.java
+++ b/java/src/org/broadinstitute/sting/playground/gatk/walkers/Recalibration/DinucCovariate.java
@@ -5,16 +5,42 @@ import org.broadinstitute.sting.utils.BaseUtils;
 
 import java.util.*;
 
+/*
+ * Copyright (c) 2009 The Broad Institute
+ *
+ * Permission is hereby granted, free of charge, to any person
+ * obtaining a copy of this software and associated documentation
+ * files (the "Software"), to deal in the Software without
+ * restriction, including without limitation the rights to use,
+ * copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following
+ * conditions:
+ *
+ * The above copyright notice and this permission notice shall be
+ * included in all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
+ * OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
+ * HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
+ * WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
+ * OTHER DEALINGS IN THE SOFTWARE.
+ */
+
 /**
  * Created by IntelliJ IDEA.
  * User: rpoplin
  * Date: Nov 3, 2009
  */
+
 public class DinucCovariate implements Covariate {
 
     public static ArrayList<String> BASES;
 
-    public DinucCovariate() { // empty constructor is required by CovariateCounterWalker
+    public DinucCovariate() { // empty constructor is required to instantiate covariate in CovariateCounterWalker and TableRecalibrationWalker
         BASES = new ArrayList<String>();
         BASES.add("A");
         BASES.add("G");
@@ -26,7 +52,7 @@ public class DinucCovariate implements Covariate {
         BASES.add("t");
     }
     
-    public Comparable<?> getValue(SAMRecord read, int offset, char[] refBases) {
+    public Comparable getValue(SAMRecord read, int offset, char[] refBases) {
         byte[] bases = read.getReadBases();
         char base = (char)bases[offset];
         char prevBase = (char)bases[offset - 1];
@@ -36,16 +62,20 @@ public class DinucCovariate implements Covariate {
         }
         // Check if bad base, probably an 'N'
         if( !BASES.contains( String.format( "%c", prevBase ) ) || !BASES.contains( String.format( "%c", base) ) ) {
-            return null; // CovariateCounterWalker and TableRecalibrationWalker will recognize that null means skip this particular location in the read
+            return null; // CovariateCounterWalker will recognize that null means skip this particular location in the read
         } else {
             return String.format("%c%c", prevBase, base);
         }
     }
     
-    public Comparable<?> getValue(String str) {
+    public Comparable getValue(String str) {
     	return str;
     }
 
+    public int estimatedNumberOfBins() {
+        return 16;
+    }
+
     public String toString() {
         return "Dinucleotide";
     }
diff --git a/java/src/org/broadinstitute/sting/playground/gatk/walkers/Recalibration/MappingQualityCovariate.java b/java/src/org/broadinstitute/sting/playground/gatk/walkers/Recalibration/MappingQualityCovariate.java
index f258822a5..7b79fcb79 100755
--- a/java/src/org/broadinstitute/sting/playground/gatk/walkers/Recalibration/MappingQualityCovariate.java
+++ b/java/src/org/broadinstitute/sting/playground/gatk/walkers/Recalibration/MappingQualityCovariate.java
@@ -2,23 +2,53 @@ package org.broadinstitute.sting.playground.gatk.walkers.Recalibration;
 
 import net.sf.samtools.SAMRecord;
 
+/*
+ * Copyright (c) 2009 The Broad Institute
+ *
+ * Permission is hereby granted, free of charge, to any person
+ * obtaining a copy of this software and associated documentation
+ * files (the "Software"), to deal in the Software without
+ * restriction, including without limitation the rights to use,
+ * copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following
+ * conditions:
+ *
+ * The above copyright notice and this permission notice shall be
+ * included in all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
+ * OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
+ * HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
+ * WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
+ * OTHER DEALINGS IN THE SOFTWARE.
+ */
+
 /**
  * Created by IntelliJ IDEA.
  * User: rpoplin
  * Date: Nov 4, 2009
  */
+
 public class MappingQualityCovariate implements Covariate {
 
-    public MappingQualityCovariate() { // empty constructor is required by CovariateCounterWalker
+    public MappingQualityCovariate() { // empty constructor is required to instantiate covariate in CovariateCounterWalker and TableRecalibrationWalker
     }
 
-    public Comparable<?> getValue(SAMRecord read, int offset, char[] refBases) {
-        return (Integer)(read.getMappingQuality());
+    public Comparable getValue(SAMRecord read, int offset, char[] refBases) {
+        return (Integer)(read.getMappingQuality()); // cast to Object Integer is required so that return values from the two getValue methods hash to the same code
     }
     
-    public Comparable<?> getValue(String str) {
+    public Comparable getValue(String str) {
         return Integer.parseInt( str );
     }
+
+    public int estimatedNumberOfBins() {
+        return 100;
+    }
     
     public String toString() {
         return "Mapping Quality Score";
diff --git a/java/src/org/broadinstitute/sting/playground/gatk/walkers/Recalibration/MinimumNQSCovariate.java b/java/src/org/broadinstitute/sting/playground/gatk/walkers/Recalibration/MinimumNQSCovariate.java
index f18454bce..963f2490d 100644
--- a/java/src/org/broadinstitute/sting/playground/gatk/walkers/Recalibration/MinimumNQSCovariate.java
+++ b/java/src/org/broadinstitute/sting/playground/gatk/walkers/Recalibration/MinimumNQSCovariate.java
@@ -3,17 +3,43 @@ package org.broadinstitute.sting.playground.gatk.walkers.Recalibration;
 import net.sf.samtools.SAMRecord;
 import org.broadinstitute.sting.utils.QualityUtils;
 
+/*
+ * Copyright (c) 2009 The Broad Institute
+ *
+ * Permission is hereby granted, free of charge, to any person
+ * obtaining a copy of this software and associated documentation
+ * files (the "Software"), to deal in the Software without
+ * restriction, including without limitation the rights to use,
+ * copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following
+ * conditions:
+ *
+ * The above copyright notice and this permission notice shall be
+ * included in all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
+ * OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
+ * HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
+ * WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
+ * OTHER DEALINGS IN THE SOFTWARE.
+ */
+
 /**
  * Created by IntelliJ IDEA.
  * User: rpoplin
  * Date: Nov 4, 2009
  */
+
 public class MinimumNQSCovariate implements Covariate {
 
     public final static String ORIGINAL_QUAL_ATTRIBUTE_TAG = "OQ";
     protected boolean USE_ORIGINAL_QUALS;
 
-    public MinimumNQSCovariate() { // empty constructor is required by CovariateCounterWalker
+    public MinimumNQSCovariate() { // empty constructor is required to instantiate covariate in CovariateCounterWalker and TableRecalibrationWalker
         USE_ORIGINAL_QUALS = false;
     }
 
@@ -21,7 +47,7 @@ public class MinimumNQSCovariate implements Covariate {
         USE_ORIGINAL_QUALS = originalQuals;
     }
 
-    public Comparable<?> getValue(SAMRecord read, int offset, char[] refBases) {
+    public Comparable getValue(SAMRecord read, int offset, char[] refBases) {
         byte[] quals = read.getBaseQualities();
         if ( USE_ORIGINAL_QUALS && read.getAttribute(ORIGINAL_QUAL_ATTRIBUTE_TAG) != null ) {
             Object obj = read.getAttribute(ORIGINAL_QUAL_ATTRIBUTE_TAG);
@@ -41,10 +67,14 @@ public class MinimumNQSCovariate implements Covariate {
         return minQual;
     }
     
-    public Comparable<?> getValue(String str) {
+    public Comparable getValue(String str) {
         return Integer.parseInt( str );
     }
 
+    public int estimatedNumberOfBins() {
+        return 40;
+    }
+
     public String toString() {
         return "Minimum Neighborhood Quality Score";
     }
diff --git a/java/src/org/broadinstitute/sting/playground/gatk/walkers/Recalibration/NHashMap.java b/java/src/org/broadinstitute/sting/playground/gatk/walkers/Recalibration/NHashMap.java
index 6792ad349..8dd85cbde 100755
--- a/java/src/org/broadinstitute/sting/playground/gatk/walkers/Recalibration/NHashMap.java
+++ b/java/src/org/broadinstitute/sting/playground/gatk/walkers/Recalibration/NHashMap.java
@@ -2,18 +2,93 @@ package org.broadinstitute.sting.playground.gatk.walkers.Recalibration;
 
 import java.util.*;
 
+/*
+ * Copyright (c) 2009 The Broad Institute
+ *
+ * Permission is hereby granted, free of charge, to any person
+ * obtaining a copy of this software and associated documentation
+ * files (the "Software"), to deal in the Software without
+ * restriction, including without limitation the rights to use,
+ * copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following
+ * conditions:
+ *
+ * The above copyright notice and this permission notice shall be
+ * included in all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
+ * OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
+ * HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
+ * WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
+ * OTHER DEALINGS IN THE SOFTWARE.
+ */
+
 /**
  * Created by IntelliJ IDEA.
  * User: rpoplin
  * Date: Oct 30, 2009
  */
-public class NHashMap<T> extends HashMap<List<? extends Comparable<?>>, T> {
+
+public class NHashMap<T> extends HashMap<List<? extends Comparable>, T> {
 
 	private static final long serialVersionUID = 1L; //BUGBUG: what should I do here?
+    private ArrayList<ArrayList<Comparable>> keyLists;
 
-    
+    public NHashMap() {
+        super();
+        keyLists = new ArrayList<ArrayList<Comparable>>();
+    }
 
-	public static <T extends Comparable<?>> List<T> makeList(T... args) {
+    public NHashMap( int initialCapacity, float loadingFactor ) {
+        super( initialCapacity, loadingFactor );
+        keyLists = new ArrayList<ArrayList<Comparable>>();
+    }
+
+    /*
+
+    // This method is here only to help facilitate direct comparison of old and refactored recalibrator.
+    // The old recalibrator prints out it's mappings in a sorted order but the refactored recalibrator doesn't need to.
+    // Comment out this overriding method to improve performance
+    public T put(List<? extends Comparable> key, T value) {
+
+        ArrayList<Comparable> thisList;
+        for( int iii = 0; iii < key.size(); iii++ ) {
+            thisList = keyLists.get( iii );
+            if( thisList == null ) {
+                thisList = new ArrayList<Comparable>();
+            }
+            if( !thisList.contains( key.get( iii ) ) ) {
+                thisList.add( key.get(iii ) );
+            }
+        }
+        return super.put( key, value );
+    }
+
+    // This method is here only to help facilitate direct comparison of old and refactored recalibrator.
+    // The old recalibrator prints out it's mappings in a sorted order but the refactored recalibrator doesn't need to.
+    // Comment out this overriding method to improve performance
+    public Set<Map.Entry<List<? extends Comparable>, T>> entrySet() {
+        
+        for( ArrayList<Comparable> list : keyLists ) {
+            Collections.sort(list);
+        }
+
+        for( ArrayList<Comparable> list : keyLists ) {
+            for( Comparable comp : list ) {
+                // BUGBUG: unfinished
+            }
+        }
+        
+        return null;
+    }
+
+    */
+
+	public static <T extends Comparable> List<T> makeList(T... args) {
         List<T> list = new ArrayList<T>();
         for (T arg : args)
         {
diff --git a/java/src/org/broadinstitute/sting/playground/gatk/walkers/Recalibration/QualityScoreCovariate.java b/java/src/org/broadinstitute/sting/playground/gatk/walkers/Recalibration/QualityScoreCovariate.java
index 2e1097e49..b2b7692d1 100644
--- a/java/src/org/broadinstitute/sting/playground/gatk/walkers/Recalibration/QualityScoreCovariate.java
+++ b/java/src/org/broadinstitute/sting/playground/gatk/walkers/Recalibration/QualityScoreCovariate.java
@@ -3,17 +3,43 @@ package org.broadinstitute.sting.playground.gatk.walkers.Recalibration;
 import net.sf.samtools.SAMRecord;
 import org.broadinstitute.sting.utils.QualityUtils;
 
+/*
+ * Copyright (c) 2009 The Broad Institute
+ *
+ * Permission is hereby granted, free of charge, to any person
+ * obtaining a copy of this software and associated documentation
+ * files (the "Software"), to deal in the Software without
+ * restriction, including without limitation the rights to use,
+ * copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following
+ * conditions:
+ *
+ * The above copyright notice and this permission notice shall be
+ * included in all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
+ * OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
+ * HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
+ * WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
+ * OTHER DEALINGS IN THE SOFTWARE.
+ */
+
 /**
  * Created by IntelliJ IDEA.
  * User: rpoplin
  * Date: Nov 3, 2009
  */
+
 public class QualityScoreCovariate implements Covariate {
 
     public final static String ORIGINAL_QUAL_ATTRIBUTE_TAG = "OQ";
     protected boolean USE_ORIGINAL_QUALS;
 
-    public QualityScoreCovariate() { // empty constructor is required by CovariateCounterWalker
+    public QualityScoreCovariate() { // empty constructor is required to instantiate covariate in CovariateCounterWalker and TableRecalibrationWalker
         USE_ORIGINAL_QUALS = false;
     }
 
@@ -21,7 +47,7 @@ public class QualityScoreCovariate implements Covariate {
         USE_ORIGINAL_QUALS = originalQuals;
     }
 
-    public Comparable<?> getValue(SAMRecord read, int offset, char[] refBases) {
+    public Comparable getValue(SAMRecord read, int offset, char[] refBases) {
         byte[] quals = read.getBaseQualities();
         if ( USE_ORIGINAL_QUALS && read.getAttribute(ORIGINAL_QUAL_ATTRIBUTE_TAG) != null ) {
             Object obj = read.getAttribute(ORIGINAL_QUAL_ATTRIBUTE_TAG);
@@ -32,12 +58,16 @@ public class QualityScoreCovariate implements Covariate {
             }
         }
 
-        return ((Integer)((int)quals[offset]));
+        return ((Integer)((int)quals[offset])); // cast to Object Integer is required so that return values from the two getValue methods hash to the same code
     }
     
-    public Comparable<?> getValue(String str) {
+    public Comparable getValue(String str) {
         return Integer.parseInt( str );
     }
+
+    public int estimatedNumberOfBins() {
+        return 40;
+    }
     
     public String toString() {
         return "Reported Quality Score";
diff --git a/java/src/org/broadinstitute/sting/playground/gatk/walkers/Recalibration/ReadGroupCovariate.java b/java/src/org/broadinstitute/sting/playground/gatk/walkers/Recalibration/ReadGroupCovariate.java
index 261eb8aa8..beaf697c5 100755
--- a/java/src/org/broadinstitute/sting/playground/gatk/walkers/Recalibration/ReadGroupCovariate.java
+++ b/java/src/org/broadinstitute/sting/playground/gatk/walkers/Recalibration/ReadGroupCovariate.java
@@ -2,24 +2,54 @@ package org.broadinstitute.sting.playground.gatk.walkers.Recalibration;
 
 import net.sf.samtools.SAMRecord;
 
+/*
+ * Copyright (c) 2009 The Broad Institute
+ *
+ * Permission is hereby granted, free of charge, to any person
+ * obtaining a copy of this software and associated documentation
+ * files (the "Software"), to deal in the Software without
+ * restriction, including without limitation the rights to use,
+ * copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following
+ * conditions:
+ *
+ * The above copyright notice and this permission notice shall be
+ * included in all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
+ * OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
+ * HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
+ * WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
+ * OTHER DEALINGS IN THE SOFTWARE.
+ */
+
 /**
  * Created by IntelliJ IDEA.
  * User: rpoplin
  * Date: Oct 30, 2009
  */
+
 public class ReadGroupCovariate implements Covariate{
 
-    public ReadGroupCovariate() { // empty constructor is required by CovariateCounterWalker
+    public ReadGroupCovariate() { // empty constructor is required to instantiate covariate in CovariateCounterWalker and TableRecalibrationWalker
     }
 
-    public Comparable<?> getValue(SAMRecord read, int offset, char[] refBases) {
+    public Comparable getValue(SAMRecord read, int offset, char[] refBases) {
         return read.getReadGroup().getReadGroupId();
     }
     
-    public Comparable<?> getValue(String str) {
+    public Comparable getValue(String str) {
     	return str;
     }
 
+    public int estimatedNumberOfBins() {
+        return 300;
+    }
+
     public String toString() {
         return "Read Group";
     }
diff --git a/java/src/org/broadinstitute/sting/playground/gatk/walkers/Recalibration/RecalDataManager.java b/java/src/org/broadinstitute/sting/playground/gatk/walkers/Recalibration/RecalDataManager.java
index 7e257a148..63af6315a 100755
--- a/java/src/org/broadinstitute/sting/playground/gatk/walkers/Recalibration/RecalDataManager.java
+++ b/java/src/org/broadinstitute/sting/playground/gatk/walkers/Recalibration/RecalDataManager.java
@@ -5,6 +5,31 @@ import org.broadinstitute.sting.utils.QualityUtils;
 
 import java.util.*;
 
+/*
+ * Copyright (c) 2009 The Broad Institute
+ *
+ * Permission is hereby granted, free of charge, to any person
+ * obtaining a copy of this software and associated documentation
+ * files (the "Software"), to deal in the Software without
+ * restriction, including without limitation the rights to use,
+ * copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following
+ * conditions:
+ *
+ * The above copyright notice and this permission notice shall be
+ * included in all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
+ * OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
+ * HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
+ * WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
+ * OTHER DEALINGS IN THE SOFTWARE.
+ */
+
 /**
  * Created by IntelliJ IDEA.
  * User: rpoplin
@@ -19,8 +44,9 @@ public class RecalDataManager {
     public boolean collapsedTablesCreated;
     public NHashMap<Double> dataSumExpectedErrors;
 
-    RecalDataManager() {
-        data = new NHashMap<RecalDatum>();
+    RecalDataManager( int estimatedCapacity ) {
+        data = new NHashMap<RecalDatum>( estimatedCapacity, 0.95f ); // second arg is the 'loading factor',
+                                                                     //   a number to monkey around with when optimizing performace of the HashMap
         collapsedTablesCreated = false;
     }
 
@@ -37,17 +63,17 @@ public class RecalDataManager {
         // preallocate for use in for loops below
         RecalDatum thisDatum;
         RecalDatum collapsedDatum;
-        List<? extends Comparable<?>> key;
-        ArrayList<Comparable<?>> newKey;
+        List<? extends Comparable> key;
+        ArrayList<Comparable> newKey;
         Double sumExpectedErrors;
 
         // for every data point in the map
-        for( Map.Entry<List<? extends Comparable<?>>,RecalDatum> entry : data.entrySet() ) {
+        for( Map.Entry<List<? extends Comparable>,RecalDatum> entry : data.entrySet() ) {
             thisDatum = entry.getValue();
             key = entry.getKey();
             
             // create dataCollapsedReadGroup, the table where everything except read group has been collapsed
-            newKey = new ArrayList<Comparable<?>>();
+            newKey = new ArrayList<Comparable>();
             newKey.add( key.get(0) ); // make a new key with just the read group
             collapsedDatum = dataCollapsedReadGroup.get( newKey );
             if( collapsedDatum == null ) {
@@ -57,7 +83,7 @@ public class RecalDataManager {
                 collapsedDatum.increment( thisDatum );
             }
             
-            newKey = new ArrayList<Comparable<?>>();
+            newKey = new ArrayList<Comparable>();
             newKey.add( key.get(0) ); // make a new key with just the read group
             sumExpectedErrors = dataSumExpectedErrors.get( newKey );
             if( sumExpectedErrors == null ) {
@@ -69,7 +95,7 @@ public class RecalDataManager {
                 dataSumExpectedErrors.put( newKey, sumExpectedErrors );
             }
 
-            newKey = new ArrayList<Comparable<?>>();
+            newKey = new ArrayList<Comparable>();
             // create dataCollapsedQuality, the table where everything except read group and quality score has been collapsed
             newKey.add( key.get(0) ); // make a new key with the read group ...
             newKey.add( key.get(1) ); //                                    and quality score
@@ -83,7 +109,7 @@ public class RecalDataManager {
 
             // create dataCollapsedByCovariate's, the tables where everything except read group, quality score, and given covariate has been collapsed
             for( int iii = 0; iii < numCovariates - 2; iii++ ) { // readGroup and QualityScore aren't counted
-                newKey = new ArrayList<Comparable<?>>();
+                newKey = new ArrayList<Comparable>();
                 newKey.add( key.get(0) ); // make a new key with the read group ...
                 newKey.add( key.get(1) ); //                                    and quality score ...
                 newKey.add( key.get(iii + 2) ); //                                                    and the given covariate
diff --git a/java/src/org/broadinstitute/sting/playground/gatk/walkers/Recalibration/RecalDatum.java b/java/src/org/broadinstitute/sting/playground/gatk/walkers/Recalibration/RecalDatum.java
index 098ed5a2e..d67eede7a 100755
--- a/java/src/org/broadinstitute/sting/playground/gatk/walkers/Recalibration/RecalDatum.java
+++ b/java/src/org/broadinstitute/sting/playground/gatk/walkers/Recalibration/RecalDatum.java
@@ -5,6 +5,31 @@ import org.broadinstitute.sting.utils.QualityUtils;
 
 import java.util.*;
 
+/*
+ * Copyright (c) 2009 The Broad Institute
+ *
+ * Permission is hereby granted, free of charge, to any person
+ * obtaining a copy of this software and associated documentation
+ * files (the "Software"), to deal in the Software without
+ * restriction, including without limitation the rights to use,
+ * copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following
+ * conditions:
+ *
+ * The above copyright notice and this permission notice shall be
+ * included in all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
+ * OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
+ * HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
+ * WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
+ * OTHER DEALINGS IN THE SOFTWARE.
+ */
+
 /**
  * Created by IntelliJ IDEA.
  * User: rpoplin
diff --git a/java/src/org/broadinstitute/sting/playground/gatk/walkers/Recalibration/TableRecalibrationWalker.java b/java/src/org/broadinstitute/sting/playground/gatk/walkers/Recalibration/TableRecalibrationWalker.java
index 0876e9f57..60d884ff9 100755
--- a/java/src/org/broadinstitute/sting/playground/gatk/walkers/Recalibration/TableRecalibrationWalker.java
+++ b/java/src/org/broadinstitute/sting/playground/gatk/walkers/Recalibration/TableRecalibrationWalker.java
@@ -13,6 +13,31 @@ import java.util.regex.Pattern;
 import java.io.File;
 import java.io.FileNotFoundException;
 
+/*
+ * Copyright (c) 2009 The Broad Institute
+ *
+ * Permission is hereby granted, free of charge, to any person
+ * obtaining a copy of this software and associated documentation
+ * files (the "Software"), to deal in the Software without
+ * restriction, including without limitation the rights to use,
+ * copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following
+ * conditions:
+ *
+ * The above copyright notice and this permission notice shall be
+ * included in all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
+ * OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
+ * HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
+ * WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
+ * OTHER DEALINGS IN THE SOFTWARE.
+ */
+
 /**
  * Created by IntelliJ IDEA.
  * User: rpoplin
@@ -56,14 +81,14 @@ public class TableRecalibrationWalker extends ReadWalker<SAMRecord, SAMFileWrite
 
         int lineNumber = 0;
         boolean foundAllCovariates = false;
-        dataManager = new RecalDataManager();
+        int estimatedCapacity = 1;
 
         // Read in the covariates that were used from the input file
         requestedCovariates = new ArrayList<Covariate>();
 
 
         // Read in the data from the csv file and populate the map
-        out.print( "Reading in the data from input file..." );
+        logger.info( "Reading in the data from input file..." );
 
         try {
             for ( String line : new xReadLines(new File( RECAL_FILE )) ) {
@@ -80,6 +105,8 @@ public class TableRecalibrationWalker extends ReadWalker<SAMRecord, SAMFileWrite
                                 try {
                                     Covariate covariate = (Covariate)covClass.newInstance();
                                     requestedCovariates.add( covariate );
+                                    estimatedCapacity *= covariate.estimatedNumberOfBins();
+                                    
                                 } catch ( InstantiationException e ) {
                                     throw new StingException( String.format("Can not instantiate covariate class '%s': must be concrete class.", covClass.getSimpleName()) );
                                 } catch ( IllegalAccessException e ) {
@@ -100,6 +127,8 @@ public class TableRecalibrationWalker extends ReadWalker<SAMRecord, SAMFileWrite
                         foundAllCovariates = true;
                         logger.info( "The covariates being used here: " );
                         logger.info( requestedCovariates );
+                        dataManager = new RecalDataManager( estimatedCapacity );
+
                     }
                     addCSVData(line);
                 }
@@ -110,12 +139,12 @@ public class TableRecalibrationWalker extends ReadWalker<SAMRecord, SAMFileWrite
         } catch ( NumberFormatException e ) {
             throw new RuntimeException("Error parsing recalibration data at line " + lineNumber, e);
         }
-        out.println( "...done!" );
+        logger.info( "...done!" );
 
         if( MODE == RecalibrationMode.SEQUENTIAL ) {
-            out.print( "Creating collapsed tables for use in sequential calculation..." );
+        	logger.info( "Creating collapsed tables for use in sequential calculation..." );
             dataManager.createCollapsedTables( requestedCovariates.size() );
-            out.println( "...done!" );
+            logger.info( "...done!" );
         }
         
         //System.out.println(dataManager.getCollapsedTable(1));
@@ -123,7 +152,7 @@ public class TableRecalibrationWalker extends ReadWalker<SAMRecord, SAMFileWrite
 
     private void addCSVData(String line) {
         String[] vals = line.split(",");
-        ArrayList<Comparable<?>> key = new ArrayList<Comparable<?>>();
+        ArrayList<Comparable> key = new ArrayList<Comparable>();
         Covariate cov; // preallocated for use in for loop below
         int iii;
         for( iii = 0; iii < requestedCovariates.size(); iii++ ) {
@@ -149,53 +178,44 @@ public class TableRecalibrationWalker extends ReadWalker<SAMRecord, SAMFileWrite
         byte[] recalQuals = originalQuals.clone();
 
         // For each base in the read
-        Comparable<?> keyElement; // preallocate for use in for loops below
         for( int iii = 1; iii < read.getReadLength() - 1; iii++ ) { // skip first and last base because there is no dinuc
-            ArrayList<Comparable<?>> key = new ArrayList<Comparable<?>>();
-            boolean badKey = false;
+            List<Comparable> key = new ArrayList<Comparable>();
             for( Covariate covariate : requestedCovariates ) {
-                keyElement = covariate.getValue( read, iii, refBases );
-                if ( keyElement != null ) {
-                    key.add( keyElement );
-                } else {
-                    badKey = true;
-                }
+                key.add( covariate.getValue( read, iii, refBases ) );
             }
 
-            if( !badKey ) {
-                if( MODE == RecalibrationMode.COMBINATORIAL ) {
-                    RecalDatum datum = dataManager.data.get( key );
-                    if( datum != null ) { // if we have data for this combination of covariates then recalibrate the quality score otherwise do nothing
-                        recalQuals[iii] = datum.empiricalQualByte( SMOOTHING );
-                    }
-                } else if( MODE == RecalibrationMode.SEQUENTIAL ) {
-                    recalQuals[iii] = performSequentialQualityCalculation( key );
-                } else {
-                    throw new StingException( "Specified RecalibrationMode is not supported: " + MODE );
+            if( MODE == RecalibrationMode.COMBINATORIAL ) {
+                RecalDatum datum = dataManager.data.get( key );
+                if( datum != null ) { // if we have data for this combination of covariates then recalibrate the quality score otherwise do nothing
+                    recalQuals[iii] = datum.empiricalQualByte( SMOOTHING );
                 }
+            } else if( MODE == RecalibrationMode.SEQUENTIAL ) {
+                recalQuals[iii] = performSequentialQualityCalculation( key );
+            } else {
+                throw new StingException( "Specified RecalibrationMode is not supported: " + MODE );
+            }
 
-                // Do some error checking on the new quality score
-                if ( recalQuals[iii]  <= 0 || recalQuals[iii]  > QualityUtils.MAX_REASONABLE_Q_SCORE ) {
-                    throw new StingException( "Assigning bad quality score " + key + " => " +  recalQuals[iii] );
-                }
+            // Do some error checking on the new quality score
+            if ( recalQuals[iii]  <= 0 || recalQuals[iii]  > QualityUtils.MAX_REASONABLE_Q_SCORE ) {
+                throw new StingException( "Assigning bad quality score " + key + " => " +  recalQuals[iii] );
             }
         }
 
         preserveQScores( originalQuals, recalQuals ); // overwrite the work done if original quality score is too low
         read.setBaseQualities(recalQuals); // overwrite old qualities with new recalibrated qualities
-        if ( read.getAttribute(ORIGINAL_QUAL_ATTRIBUTE_TAG) == null ) { // save the old qualities if there is room in the read
+        if ( read.getAttribute(ORIGINAL_QUAL_ATTRIBUTE_TAG) == null ) { // save the old qualities if the tag isn't already taken in the read
             read.setAttribute(ORIGINAL_QUAL_ATTRIBUTE_TAG, QualityUtils.phredToFastq(originalQuals));
         }
 
         return read;
     }
 
-    private byte performSequentialQualityCalculation( ArrayList<? extends Comparable<?>> key ) {
+    private byte performSequentialQualityCalculation( List<? extends Comparable> key ) {
 
         byte qualFromRead = Byte.parseByte(key.get(1).toString());
-        ArrayList<Comparable<?>> newKey;
+        ArrayList<Comparable> newKey;
         
-        newKey = new ArrayList<Comparable<?>>();
+        newKey = new ArrayList<Comparable>();
         newKey.add( key.get(0) ); // read group
         RecalDatum globalDeltaQDatum = dataManager.getCollapsedTable(0).get( newKey );
         double globalDeltaQ = 0.0;
@@ -206,7 +226,7 @@ public class TableRecalibrationWalker extends ReadWalker<SAMRecord, SAMFileWrite
         }
         
        
-        newKey = new ArrayList<Comparable<?>>();
+        newKey = new ArrayList<Comparable>();
         newKey.add( key.get(0) ); // read group
         newKey.add( key.get(1) ); // quality score
         RecalDatum deltaQReportedDatum = dataManager.getCollapsedTable(1).get( newKey );
@@ -219,7 +239,7 @@ public class TableRecalibrationWalker extends ReadWalker<SAMRecord, SAMFileWrite
         double deltaQCovariates = 0.0;
         RecalDatum deltaQCovariateDatum;
         for( int iii = 2; iii < key.size(); iii++ ) {
-            newKey = new ArrayList<Comparable<?>>();
+            newKey = new ArrayList<Comparable>();
             newKey.add( key.get(0) ); // read group
             newKey.add( key.get(1) ); // quality score
             newKey.add( key.get(iii) ); // given covariate
@@ -236,6 +256,8 @@ public class TableRecalibrationWalker extends ReadWalker<SAMRecord, SAMFileWrite
             throw new StingException( "Illegal base quality score calculated: " + key +
                         String.format( " => %d + %.2f + %.2f + %.2f = %d", qualFromRead, globalDeltaQ, deltaQReported, deltaQCovariates, newQualityByte ) );
         }
+        
+        //System.out.println("returning: " + newQualityByte);
         return newQualityByte;
     }