StringInterpolationSequence does not need an internal SassList, use a

simple list to reduce object allocation

Author: volker

src/main/java/com/inet/sass/parser/SassList.java

@@ -167,11 +167,16 @@ public SassList evaluateFunctionsAndExpressions(ScssContext context,
     public SassList replaceVariables(ScssContext context) {
         // The actual replacing happens in LexicalUnitImpl, which also
         // implements SassListItem.
-        List<SassListItem> list = new ArrayList<SassListItem>();
-        for (SassListItem item : this) {
-            list.add(item.replaceVariables(context));
+        return new SassList(getSeparator(), replaceVariables( context, items ) );
+    }
+
+    static List<SassListItem> replaceVariables( ScssContext context, List<SassListItem> items ) {
+        int size = items.size();
+        List<SassListItem> list = new ArrayList<SassListItem>( size );
+        for( int i = 0; i < size; i++ ) {
+            list.add( items.get( i ).replaceVariables( context ) );
         }
-        return new SassList(getSeparator(), list);
+        return list;
     }
 
     @Override
@@ -237,19 +242,22 @@ public String getStringWithNesting() {
     @Override
     public SassList updateUrl(String prefix) {
         if (size() > 0) {
-            ArrayList<SassListItem> newItems = new ArrayList<SassListItem>(
-                    size());
-            for (SassListItem item : this) {
-                newItems.add(item.updateUrl(prefix));
-            }
-            SassList result = new SassList(getSeparator(), newItems);
-            result.setSourcePosition(getLineNumber(), getColumnNumber());
+            SassList result = new SassList( getSeparator(), updateUrl( items, prefix ) );
             return result;
         } else {
             return this;
         }
     }
 
+    static List<SassListItem> updateUrl( List<SassListItem> items, String prefix ) {
+        int size = items.size();
+        ArrayList<SassListItem> newItems = new ArrayList<SassListItem>( size );
+        for( int i = 0; i < size; i++ ) {
+            newItems.add( items.get( i ).updateUrl( prefix ) );
+        }
+        return newItems;
+    }
+
     @Override
     public boolean equals(Object o) {
         if (!(o instanceof SassList)) {

src/main/java/com/inet/sass/parser/StringInterpolationSequence.java

@@ -35,16 +35,16 @@
  * 
  */
 public class StringInterpolationSequence {
-    private boolean containsInterpolation = false;
-    private SassList items;
+    private boolean containsInterpolation;
+    private List<SassListItem> items;
     private String toString;
 
     /**
-     * Creates a new StringInterpolationSequence containing only the given item.
-     * 
+     * Creates a new StringInterpolationSequence containing only the given item without interpolation.
+     * @param value single string value
      */
-    public StringInterpolationSequence(String value) {
-        this(Collections.<SassListItem> singletonList(new StringItem(value)));
+    public StringInterpolationSequence( String value ) {
+        items = Collections.<SassListItem> singletonList( new StringItem( value ) );
     }
 
     /**
@@ -61,11 +61,7 @@ public StringInterpolationSequence(List<SassListItem> sequence) {
                 break;
             }
         }
-        items = new SassList(SassList.Separator.SPACE, sequence);
-    }
-
-    private StringInterpolationSequence(SassList list) {
-        this(list.getItems());
+        items = sequence;
     }
 
     /**
@@ -77,12 +73,12 @@ private StringInterpolationSequence(SassList list) {
      *            current compilation context
      * @return A new StringInterpolationSequence.
      */
-    public StringInterpolationSequence replaceVariables(ScssContext context) {
+    public StringInterpolationSequence replaceVariables( ScssContext context ) {
         if( !containsInterpolation ) {
             return this;
         }
-        SassList resultList = items.replaceVariables( context );
-        return new StringInterpolationSequence( resultList );
+
+        return new StringInterpolationSequence( SassList.replaceVariables( context, items ) );
     }
 
     /**
@@ -96,17 +92,21 @@ public StringInterpolationSequence replaceVariables(ScssContext context) {
      */
     public StringInterpolationSequence append(StringInterpolationSequence other) {
         ArrayList<SassListItem> result = new ArrayList<SassListItem>(
-                items.getItems());
-        result.addAll(other.items.getItems());
+                items);
+        result.addAll(other.items);
         return new StringInterpolationSequence(result);
     }
 
     @Override
     public String toString() {
-        if (toString == null) {
+        if( toString == null ) {
+            List<SassListItem> items = this.items;
+            if( items.size() == 1 ) {
+                return items.get( 0 ).printState();
+            }
             StringBuilder result = new StringBuilder();
-            for (SassListItem item : items) {
-                result.append(item.printState());
+            for( SassListItem item : items ) {
+                result.append( item.printState() );
             }
             toString = result.toString();
         }
@@ -129,12 +129,12 @@ public boolean containsInterpolation() {
     }
 
     public List<SassListItem> getItems() {
-        return items.getItems();
+        return items;
     }
 
     public StringInterpolationSequence updateUrl(String prefix) {
         if( containsInterpolation ) {
-            return new StringInterpolationSequence(items.updateUrl(prefix));
+            return new StringInterpolationSequence( SassList.updateUrl( items, prefix ) );
         }
         return this;
     }