Index all lua strings created from java strings.

src/core/org/luaj/vm2/Buffer.java

@@ -42,7 +42,7 @@ public final class Buffer {
 	}
 	
 	public final String toString() {
-		return new LuaString(bytes, 0, length).toString();
+		return LuaString.valueOf(bytes, 0, length).toString();
 	}
 	
 	public final void append( byte b ) {
@@ -75,7 +75,7 @@ public final class Buffer {
 	}
 	
 	public final LuaString tostring() {
-		return new LuaString( realloc( bytes, length ) );
+		return LuaString.valueOf( realloc( bytes, length ) );
 	}
 	
 	public final void ensureCapacity( int minSize ) {

src/core/org/luaj/vm2/LoadState.java

@@ -157,7 +157,7 @@ public class LoadState {
 			return null;
 		byte[] bytes = new byte[size];
 		is.readFully( bytes, 0, size );
-		return new LuaString( bytes, 0, bytes.length - 1 );
+		return LuaString.valueOf( bytes, 0, bytes.length - 1 );
 	}
 	
 	public static LuaValue longBitsToLuaNumber( long bits ) {

src/core/org/luaj/vm2/LuaString.java

@@ -26,6 +26,7 @@ import java.io.DataOutputStream;
 import java.io.IOException;
 import java.io.InputStream;
 import java.lang.ref.WeakReference;
+import java.util.Hashtable;
 
 import org.luaj.vm2.lib.StringLib;
 
@@ -37,58 +38,50 @@ public class LuaString extends LuaValue {
 	public final int    m_offset;
 	public final int    m_length;
 
-	private static final int STRINGCACHE_POW2 = 10;
-	private static final WeakReference[] stringcache 
-					= new WeakReference[1<<STRINGCACHE_POW2];
+	private static final Hashtable index_java = new Hashtable();
 
-	private static class LuaJavaString extends LuaString {
-		private final String string;
-		private LuaJavaString(String value, byte[] bytes) {
-			super(bytes);
-			string = value.intern();
-		}
-		public String toString() {
-			return string;
-		}
+	private final static LuaString index_get(Hashtable indextable, Object key) {
+		WeakReference w = (WeakReference) indextable.get(key);
+		return w!=null? (LuaString) w.get(): null;
+	}
+	
+	private final static void index_set(Hashtable indextable, Object key, LuaString value) {
+		indextable.put(key, new WeakReference(value));
 	}
 	
 	public static LuaString valueOf(String string) {
-		int h = string.hashCode();
-		int i = h & ((1<<STRINGCACHE_POW2)-1);
-		if ( stringcache[i] != null ) {
-			LuaJavaString s = (LuaJavaString) stringcache[i].get();
-			if ( s != null && s.string == string ) {
-				return s;
-			}
-		}
+		LuaString s = index_get( index_java, string );
+		if ( s != null ) return s;
 		char[] c = string.toCharArray();
 		byte[] b = new byte[lengthAsUtf8(c)];
 		encodeToUtf8(c, b, 0);
-		LuaJavaString s = new LuaJavaString(string,b);
-		stringcache[i] = new WeakReference(s);
+		s = valueOf(b, 0, b.length);
+		index_set( index_java, string, s );
 		return s;
 	}
-
-	public LuaString(byte[] bytes, int offset, int length) {
-		this.m_bytes = bytes;
-		this.m_offset = offset;
-		this.m_length = length;
+	
+	public static LuaString valueOf(byte[] bytes, int off, int len) { 
+		return new LuaString(bytes, off, len);
 	}
 	
-	public LuaString(byte[] bytes) {
-		this.m_bytes = bytes;
-		this.m_offset = 0;
-		this.m_length = bytes.length;
-	}
-
 	public static LuaString valueOf(char[] bytes) {
 		int n = bytes.length;
 		byte[] b = new byte[n];
 		for ( int i=0; i<n; i++ )
 			b[i] = (byte) bytes[i];
-		return new LuaString(b, 0, n);
+		return valueOf(b, 0, n);
 	}
 	
+	public static LuaString valueOf(byte[] bytes) {
+		return valueOf(bytes, 0, bytes.length);
+	}
+	
+	private LuaString(byte[] bytes, int offset, int length) {
+		this.m_bytes = bytes;
+		this.m_offset = offset;
+		this.m_length = length;
+	}
+
 	public boolean isstring() {
 		return true; 
 	}

src/core/org/luaj/vm2/LuaValue.java

@@ -306,9 +306,9 @@ public class LuaValue extends Varargs {
 	public static LuaInteger  valueOf(int i)        { return LuaInteger.valueOf(i); }
 	public static LuaNumber   valueOf(double d)     { return LuaDouble.valueOf(d); };
 	public static LuaString valueOf(String s)     { return LuaString.valueOf(s); }
-	public static LuaString valueOf(byte[] bytes) { return new LuaString(bytes); }
+	public static LuaString valueOf(byte[] bytes) { return LuaString.valueOf(bytes); }
 	public static LuaString valueOf(byte[] bytes, int off, int len) { 
-		return new LuaString(bytes,off,len); 
+		return LuaString.valueOf(bytes,off,len); 
 	}
 	
 	// table initializers

src/core/org/luaj/vm2/lib/IoLib.java

@@ -398,7 +398,7 @@ public class IoLib extends OneArgFunction {
 		int r;
 		if ( ( r = f.read(b,0,b.length) ) < 0 )
 			return NIL;
-		return valueOf(b, 0, r);
+		return LuaString.valueOf(b, 0, r);
 	}
 	public static LuaValue freaduntil(File f,int delim) throws IOException {
 		ByteArrayOutputStream baos = new ByteArrayOutputStream();
@@ -415,7 +415,7 @@ public class IoLib extends OneArgFunction {
 		}
 		return ( c < 0 && baos.size() == 0 )? 
 			(LuaValue) NIL:
-			(LuaValue) valueOf(baos.toByteArray());
+			(LuaValue) LuaString.valueOf(baos.toByteArray());
 	}
 	public static LuaValue freadline(File f) throws IOException {
 		return freaduntil(f,'\n');

src/core/org/luaj/vm2/lib/StringLib.java

@@ -127,7 +127,7 @@ public class StringLib extends OneArgFunction {
 			if (c<0 || c>=256) error(a, "invalid value");
 			bytes[i] = (byte) c;
 		}
-		return valueOf( bytes );
+		return LuaString.valueOf( bytes );
 	}
 		
 	/** 
@@ -144,7 +144,7 @@ public class StringLib extends OneArgFunction {
 		ByteArrayOutputStream baos = new ByteArrayOutputStream();
 		try {
 			DumpState.dump( ((LuaClosure)f).p, baos, true );
-			return valueOf(baos.toByteArray());
+			return LuaString.valueOf(baos.toByteArray());
 		} catch (IOException e) {
 			return error( e.getMessage() );
 		}
@@ -625,7 +625,7 @@ public class StringLib extends OneArgFunction {
 		for ( int offset = 0; offset < bytes.length; offset += len ) {
 			s.copyInto( 0, bytes, offset, len );
 		}
-		return valueOf( bytes );
+		return LuaString.valueOf( bytes );
 	}
 
 	/** 
@@ -639,7 +639,7 @@ public class StringLib extends OneArgFunction {
 		byte[] b = new byte[n];
 		for ( int i=0, j=n-1; i<n; i++, j-- )
 			b[j] = (byte) s.luaByte(i);
-		return valueOf( b );
+		return LuaString.valueOf( b );
 	}
 
 	/**