diff --git a/jode/jode/flow/CatchBlock.java b/jode/jode/flow/CatchBlock.java
index 7f4ebcc..69cbc7b 100644
--- a/jode/jode/flow/CatchBlock.java
+++ b/jode/jode/flow/CatchBlock.java
@@ -24,6 +24,7 @@ import jode.expr.Expression;
 import jode.expr.LocalLoadOperator;
 import jode.expr.LocalStoreOperator;
 import jode.expr.StoreInstruction;
+import jode.util.SimpleSet;
 
 /**
  * 
@@ -120,10 +121,10 @@ public class CatchBlock extends StructuredBlock {
 	super.removePush();
     }
 
-    public VariableSet getUsed() {
-	used = new VariableSet();
+    public SimpleSet getDeclarables() {
+	SimpleSet used = new SimpleSet();
 	if (exceptionLocal != null)
-	    used.addElement(exceptionLocal);
+	    used.add(exceptionLocal);
 	return used;
     }
     
@@ -133,7 +134,7 @@ public class CatchBlock extends StructuredBlock {
      * is marked as used, but not done.
      * @param done The set of the already declare variables.
      */
-    public void makeDeclaration(VariableSet done) {
+    public void makeDeclaration(SimpleSet done) {
 	super.makeDeclaration(done);
 	/* Normally we have to declare our exceptionLocal.  This
 	 * is automatically done in dumpSource.
@@ -142,7 +143,7 @@ public class CatchBlock extends StructuredBlock {
 	 * this block.  In that case we do a transformation.
 	 */
 	if (declare.contains(exceptionLocal))
-	    declare.removeElement(exceptionLocal);
+	    declare.remove(exceptionLocal);
 	else {
 	    LocalInfo dummyLocal = new LocalInfo();
 	    Expression store = new StoreInstruction
diff --git a/jode/jode/flow/FlowBlock.java b/jode/jode/flow/FlowBlock.java
index 304e856..298ebc4 100644
--- a/jode/jode/flow/FlowBlock.java
+++ b/jode/jode/flow/FlowBlock.java
@@ -27,6 +27,7 @@ import jode.decompiler.LocalInfo;
 import jode.expr.Expression;
 import jode.expr.CombineableOperator;
 import jode.util.SimpleDictionary;
+import jode.util.SimpleSet;
 
 /**
  * A flow block is the structure of which the flow graph consists.  A
@@ -1489,14 +1490,19 @@ public class FlowBlock {
 	    nextByAddr.removeOnetimeLocals();
     }
 
-    public void makeDeclaration(VariableSet param) {
-	in.merge(param);
-	in.subtract(param);
+    public void mergeParams(LocalInfo[] param) {
+	VariableSet paramSet = new VariableSet(param);
+	in.merge(paramSet);
+	in.subtract(paramSet);
+    }
+
+    public void makeDeclaration(LocalInfo[] param) {
 	block.propagateUsage();
-	Enumeration enum = param.elements();
-	while (enum.hasMoreElements())
-	    ((LocalInfo) enum.nextElement()).guessName();
-	block.makeDeclaration(param);
+	SimpleSet declared = new SimpleSet();
+	for (int i=0; i < param.length; i++) {
+	    declared.add(param[i]);
+	}
+	block.makeDeclaration(declared);
     }
 
     public void simplify() {
diff --git a/jode/jode/flow/IfThenElseBlock.java b/jode/jode/flow/IfThenElseBlock.java
index fd26542..0e8c07d 100644
--- a/jode/jode/flow/IfThenElseBlock.java
+++ b/jode/jode/flow/IfThenElseBlock.java
@@ -22,6 +22,7 @@ import jode.decompiler.LocalInfo;
 import jode.decompiler.TabbedPrintWriter;
 import jode.expr.Expression;
 import jode.type.Type;
+import jode.util.SimpleSet;
 
 /**
  * An IfThenElseBlock is the structured block representing an if
@@ -131,9 +132,9 @@ public class IfThenElseBlock extends StructuredBlock {
 	    elseBlock.removePush();
     }
 
-    public VariableSet getUsed() {
-	used = new VariableSet();
-	cond.fillInGenSet(null, used);
+    public SimpleSet getDeclarables() {
+	SimpleSet used = new SimpleSet();
+	cond.fillDeclarables(used);
 	return used;
     }
 
diff --git a/jode/jode/flow/InstructionBlock.java b/jode/jode/flow/InstructionBlock.java
index 0455a5b..60953d2 100644
--- a/jode/jode/flow/InstructionBlock.java
+++ b/jode/jode/flow/InstructionBlock.java
@@ -24,6 +24,7 @@ import jode.decompiler.LocalInfo;
 import jode.expr.Expression;
 import jode.expr.StoreInstruction;
 import jode.expr.LocalStoreOperator;
+import jode.util.SimpleSet;
 
 /**
  * This is the structured block for atomic instructions.
@@ -100,7 +101,7 @@ public class InstructionBlock extends InstructionContainer {
      * variable.  In that case mark this as declaration and return the 
      * variable.
      */
-    public void checkDeclaration(VariableSet declareSet) {
+    public void checkDeclaration(SimpleSet declareSet) {
         if (instr instanceof StoreInstruction
 	    && (((StoreInstruction)instr).getLValue() 
 		instanceof LocalStoreOperator)) {
@@ -114,7 +115,7 @@ public class InstructionBlock extends InstructionContainer {
 		 */
 		isDeclaration = true;
 		storeOp.getSubExpressions()[1].makeInitializer();
-		declareSet.removeElement(local);
+		declareSet.remove(local);
 	    }
 	}
     }
@@ -125,7 +126,7 @@ public class InstructionBlock extends InstructionContainer {
      * is marked as used, but not done.
      * @param done The set of the already declare variables.
      */
-    public void makeDeclaration(VariableSet done) {
+    public void makeDeclaration(SimpleSet done) {
 	super.makeDeclaration(done);
 	checkDeclaration(declare);
     }
@@ -133,16 +134,18 @@ public class InstructionBlock extends InstructionContainer {
     public void dumpInstruction(TabbedPrintWriter writer) 
 	throws java.io.IOException
     {
-	if (instr.getType() != Type.tVoid)
-	    writer.print("PUSH ");
-        else if (isDeclaration) {
+        if (isDeclaration) {
+	    StoreInstruction store = (StoreInstruction) instr;
             LocalInfo local = 
-		((LocalStoreOperator) ((StoreInstruction) instr).getLValue())
-		.getLocalInfo();
-	    writer.printType(local.getType().getHint());
-	    writer.print(" ");
+		((LocalStoreOperator) store.getLValue()).getLocalInfo();
+	    local.dumpDeclaration(writer);
+	    writer.print(" = ");
+	    store.getSubExpressions()[1].dumpExpression(writer);
+	} else {
+	    if (instr.getType() != Type.tVoid)
+		writer.print("PUSH ");
+	    instr.dumpExpression(writer);
 	}
-	instr.dumpExpression(writer);
 	writer.println(";");
     }
 }
diff --git a/jode/jode/flow/InstructionContainer.java b/jode/jode/flow/InstructionContainer.java
index be3b1c5..355b5a0 100644
--- a/jode/jode/flow/InstructionContainer.java
+++ b/jode/jode/flow/InstructionContainer.java
@@ -21,6 +21,7 @@ package jode.flow;
 import jode.decompiler.LocalInfo;
 import jode.expr.Expression;
 import jode.expr.LocalVarOperator;
+import jode.util.SimpleSet;
 
 /**
  * This is a method for block containing a single instruction.
@@ -69,10 +70,10 @@ public abstract class InstructionContainer extends StructuredBlock {
 	    instr.fillInGenSet(in, gen);
     }
 
-    public VariableSet getUsed() {
-	used = new VariableSet();
+    public SimpleSet getDeclarables() {
+	SimpleSet used = new SimpleSet();
 	if (instr != null)
-	    instr.fillInGenSet(null, used);
+	    instr.fillDeclarables(used);
 	return used;
     }
 
diff --git a/jode/jode/flow/LoopBlock.java b/jode/jode/flow/LoopBlock.java
index f4b3d09..84910ba 100644
--- a/jode/jode/flow/LoopBlock.java
+++ b/jode/jode/flow/LoopBlock.java
@@ -26,6 +26,7 @@ import jode.expr.ConstOperator;
 import jode.expr.StoreInstruction;
 import jode.expr.LocalStoreOperator;
 import jode.expr.CombineableOperator;
+import jode.util.SimpleSet;
 
 /**
  * This is the structured block for an Loop block.
@@ -200,25 +201,25 @@ public class LoopBlock extends StructuredBlock implements BreakableBlock {
      * Remove all variables from set, that we can declare inside the
      * loop-block.  This is the initializer for for-blocks.
      */
-    public void removeLocallyDeclareable(VariableSet set) {
+    public void removeLocallyDeclareable(SimpleSet set) {
 	if (type == FOR && initInstr instanceof StoreInstruction) {
 	    StoreInstruction storeOp = (StoreInstruction) initInstr;
 	    if (storeOp.getLValue() instanceof LocalStoreOperator) {
 		LocalInfo local = 
 		    ((LocalStoreOperator) storeOp.getLValue()).getLocalInfo();
-		set.removeElement(local);
+		set.remove(local);
 	    }
 	}
     }
 
-    public VariableSet getUsed() {
-	used = new VariableSet();
+    public SimpleSet getDeclarables() {
+	SimpleSet used = new SimpleSet();
         if (type == FOR) {
-	    incrInstr.fillInGenSet(null, used);
+	    incrInstr.fillDeclarables(used);
 	    if (initInstr != null)
-		initInstr.fillInGenSet(null, used);
+		initInstr.fillDeclarables(used);
 	}
-	cond.fillInGenSet(null, used);
+	cond.fillDeclarables(used);
         return used;
     }
 
@@ -249,7 +250,7 @@ public class LoopBlock extends StructuredBlock implements BreakableBlock {
      * variable.  In that case mark this as declaration and return the 
      * variable.
      */
-    public void checkDeclaration(VariableSet declareSet) {
+    public void checkDeclaration(SimpleSet declareSet) {
         if (initInstr instanceof StoreInstruction
 	    && (((StoreInstruction)initInstr).getLValue() 
 		instanceof LocalStoreOperator)) {
@@ -263,7 +264,7 @@ public class LoopBlock extends StructuredBlock implements BreakableBlock {
 		 */
 		isDeclaration = true;
 		storeOp.getSubExpressions()[1].makeInitializer();
-		declareSet.removeElement(local);
+		declareSet.remove(local);
 	    }
 	}
     }
@@ -274,7 +275,7 @@ public class LoopBlock extends StructuredBlock implements BreakableBlock {
      * is marked as used, but not done.
      * @param done The set of the already declare variables.
      */
-    public void makeDeclaration(VariableSet done) {
+    public void makeDeclaration(SimpleSet done) {
 	super.makeDeclaration(done);
         if (type == FOR && initInstr != null)
 	    checkDeclaration(declare);
diff --git a/jode/jode/flow/RetBlock.java b/jode/jode/flow/RetBlock.java
index 8bb6ba1..f90e97b 100644
--- a/jode/jode/flow/RetBlock.java
+++ b/jode/jode/flow/RetBlock.java
@@ -19,6 +19,7 @@
 
 package jode.flow;
 import jode.decompiler.LocalInfo;
+import jode.util.SimpleSet;
 
 /** 
  * This block represents a ret instruction.  A ret instruction is
@@ -58,9 +59,9 @@ public class RetBlock extends StructuredBlock {
 	return null;
     }
 
-    public VariableSet getUsed() {
-	used = new VariableSet();
-	used.addElement(local);
+    public SimpleSet getDeclarables() {
+	SimpleSet used = new SimpleSet();
+	used.add(local);
 	return used;
     }
 
diff --git a/jode/jode/flow/SequentialBlock.java b/jode/jode/flow/SequentialBlock.java
index 5a9b47d..f898973 100644
--- a/jode/jode/flow/SequentialBlock.java
+++ b/jode/jode/flow/SequentialBlock.java
@@ -22,6 +22,7 @@ import jode.decompiler.TabbedPrintWriter;
 import jode.decompiler.LocalInfo;
 import jode.expr.LocalStoreOperator;
 import jode.expr.StoreInstruction;
+import jode.util.SimpleSet;
 
 /**
  * A sequential block combines exactly two structured blocks to a new
@@ -167,22 +168,23 @@ public class SequentialBlock extends StructuredBlock {
      * @return all locals that are used in this block or in some sub
      * block (this is <i>not</i> the used set).
      */
-    public VariableSet propagateUsage() {
-	used = new VariableSet();
-        VariableSet allUse = new VariableSet();
-	VariableSet childUse0 = subBlocks[0].propagateUsage();
-	VariableSet childUse1 = subBlocks[1].propagateUsage();
+    public SimpleSet propagateUsage() {
+	used = getDeclarables();
+        SimpleSet allUse = new SimpleSet();
+	SimpleSet childUse0 = subBlocks[0].propagateUsage();
+	SimpleSet childUse1 = subBlocks[1].propagateUsage();
 	/* All variables used somewhere inside both sub blocks, are
 	 * used in this block, too.  
 	 * Also the variables used in first block are used in this
 	 * block, except when it can be declared locally.  (Note that
 	 * subBlocks[0].used != childUse0) */
-	used.unionExact(subBlocks[0].used);
+	used.addAll(subBlocks[0].used);
 	if (subBlocks[0] instanceof LoopBlock)
 	    ((LoopBlock) subBlocks[0]).removeLocallyDeclareable(used);
-	used.unionExact(childUse0.intersectExact(childUse1));
-	allUse.unionExact(childUse0);
-	allUse.unionExact(childUse1);
+	allUse.addAll(childUse0);
+	allUse.addAll(childUse1);
+	childUse0.retainAll(childUse1);
+	used.addAll(childUse0);
         return allUse;
     }
 
@@ -192,7 +194,7 @@ public class SequentialBlock extends StructuredBlock {
      * is marked as used, but not done.
      * @param done The set of the already declare variables.
      */
-    public void makeDeclaration(VariableSet done) {
+    public void makeDeclaration(SimpleSet done) {
 	super.makeDeclaration(done);
 	if (subBlocks[0] instanceof InstructionBlock)
 	    /* An instruction block may declare a variable for us.
diff --git a/jode/jode/flow/StructuredBlock.java b/jode/jode/flow/StructuredBlock.java
index 87e582d..b847753 100644
--- a/jode/jode/flow/StructuredBlock.java
+++ b/jode/jode/flow/StructuredBlock.java
@@ -22,6 +22,10 @@ import jode.AssertError;
 import jode.GlobalOptions;
 import jode.decompiler.TabbedPrintWriter;
 import jode.decompiler.LocalInfo;
+import jode.decompiler.Declarable;
+import jode.util.SimpleSet;
+
+import java.util.Enumeration;
 
 /**
  * A structured block is the building block of the source programm.
@@ -63,17 +67,17 @@ public abstract class StructuredBlock {
      */
 
     /**
-     * The variable set containing all variables that are used in
-     * this block.  You must set this, before calling super.propagateUsage.
+     * The SimpleSet containing all Declarables that are used in this
+     * block. 
      */
-    VariableSet used;
+    SimpleSet used;
 
     /**
-     * The variable set containing all variables we must declare.
+     * The SimpleSet containing all Declarables we must declare.
      * The analyzation is done in makeDeclaration
      */
-    VariableSet declare;
-    VariableSet done;
+    SimpleSet declare;
+    SimpleSet done;
 
     /**
      * The surrounding structured block.  If this is the outermost
@@ -339,8 +343,8 @@ public abstract class StructuredBlock {
 	return false;
     }
 
-    public VariableSet getUsed() {
-	return new VariableSet();
+    public SimpleSet getDeclarables() {
+	return new SimpleSet();
     }
 
     /**
@@ -351,17 +355,21 @@ public abstract class StructuredBlock {
      *
      * @return all locals that are used in this block or in some sub
      * block (this is <i>not</i> the used set).  */
-    public VariableSet propagateUsage() {
-	used = getUsed();
+    public SimpleSet propagateUsage() {
+	used = getDeclarables();
         StructuredBlock[] subs = getSubBlocks();
-        VariableSet allUse = (VariableSet) used.clone();
+        SimpleSet allUse = (SimpleSet) used.clone();
         for (int i=0; i<subs.length; i++) {
-            VariableSet childUse = subs[i].propagateUsage();
+            SimpleSet childUse = subs[i].propagateUsage();
             /* All variables used in more than one sub blocks, are
              * used in this block, too.  
              */
-            used.unionExact(allUse.intersectExact(childUse));
-            allUse.unionExact(childUse);
+	    Enumeration enum = childUse.elements();
+	    SimpleSet intersection = new SimpleSet();
+	    intersection.addAll(childUse);
+	    intersection.retainAll(allUse);
+	    used.addAll(intersection);
+	    allUse.addAll(childUse);
         }
         return allUse;
     }
@@ -432,72 +440,84 @@ public abstract class StructuredBlock {
      *
      * @param done The set of the already declare variables.
      */
-    public void makeDeclaration(VariableSet done) {
-	this.done = (VariableSet) done.clone();
-	declare = new VariableSet();
+    public void makeDeclaration(SimpleSet done) {
+//  	System.err.println("makeDeclaration: done = "+done);
+	this.done = (SimpleSet) done.clone();
+	declare = new SimpleSet();
 	java.util.Enumeration enum = used.elements();
+//  	System.err.println("makeDeclaration: used = "+used);
     next_used:
 	while (enum.hasMoreElements()) {
-	    LocalInfo local = (LocalInfo) enum.nextElement();
-
-	    /* First generate the names for the locals, since this may
-	     * also change their types, if they are in the local
-	     * variable table.
-	     */
-	    String localName = local.guessName();
-
-	    int size = done.size();
-	    // Check if this local is already declared.
-	    for (int i=0; i< size; i++) {
-		LocalInfo prevLocal = done.elementAt(i);
-		if (prevLocal.equals(local))
-		    continue next_used;
-	    }
-
-	    // Merge with all locals in this block, that use the same 
-	    // slot and have compatible types and names.
-	    for (int i=0; i< size; i++) {
-		LocalInfo prevLocal = done.elementAt(i);
-		if (prevLocal.getSlot() == local.getSlot()) {
-
-		    /* XXX - I have to think about this...
-		     * there may be a case where this leads to type errors.
-		     * TODO: Give a formal proof ;-)
-		     * One bad thing that may happen is that the name
-		     * of prevLocal (it has already a name) doesn't match
-		     * the intersected type.
-		     *
-		     * We don't want to merge variables, whose names are
-		     * not generated by us and differ.  
-		     * 
-		     * And don't merge "this" with any other variable 
-		     * since it mustn't be written to.
-		     */
-		    if (prevLocal.getType().isOfType(local.getType())
-			&& prevLocal.getName() != "this"
-			&& (prevLocal.isNameGenerated() 
-			    || local.isNameGenerated()
-			    || localName.equals(prevLocal.getName()))) {
-			local.combineWith(prevLocal);
-			continue next_used;
+	    Declarable declarable = (Declarable) enum.nextElement();
+
+	    // Check if this is already declared.
+	    if (done.contains(declarable))
+		continue next_used;
+
+	    if (declarable instanceof LocalInfo) {
+		LocalInfo local = (LocalInfo) declarable;
+
+		/* First generate the names for the locals, since this may
+		 * also change their types, if they are in the local
+		 * variable table.
+		 */
+		String localName = local.guessName();
+		
+		// Merge with all locals in this block, that use the same 
+		// slot and have compatible types and names.
+		Enumeration doneEnum = done.elements();
+		while (doneEnum.hasMoreElements()) {
+		    Declarable previous = (Declarable) doneEnum.nextElement();
+		    if (!(previous instanceof LocalInfo))
+			continue;
+		    LocalInfo prevLocal = (LocalInfo) previous;
+		    if (prevLocal.getSlot() == local.getSlot()) {
+
+			/* XXX - I have to think about this...
+			 * there may be a case where this leads to type errors.
+			 * TODO: Give a formal proof ;-)
+			 * One bad thing that may happen is that the name
+			 * of prevLocal (it has already a name) doesn't match
+			 * the intersected type.
+			 *
+			 * We don't want to merge variables, whose names
+			 * are not generated by us and differ.  And we
+			 * don't want to merge special locals that have a
+			 * constant expression, e.g. this.
+			 */
+			if (prevLocal.getType().isOfType(local.getType())
+			    && (prevLocal.isNameGenerated() 
+				|| local.isNameGenerated()
+				|| localName.equals(prevLocal.getName()))
+			    && prevLocal.getExpression() == null
+			    && local.getExpression() == null) {
+			    local.combineWith(prevLocal);
+			    continue next_used;
+			}
 		    }
 		}
 	    }
-
-	    LocalInfo previous = done.findLocal(localName);
-	    if (previous != null) {
-		/* A name conflict happened. */
-		local.makeNameUnique();
+	    
+	    if (declarable.getName() != null) {
+		Enumeration doneEnum = done.elements();
+		while (doneEnum.hasMoreElements()) {
+		    Declarable previous = (Declarable) doneEnum.nextElement();
+		    if (declarable.getName().equals(previous.getName())) {
+			/* A name conflict happened. */
+			declarable.makeNameUnique();
+		    }
+		}
 	    }
-	    done.addElement(local);
-	    declare.addElement(local);
+	    done.add(declarable);
+	    declare.add(declarable);
 	}
+//  	System.err.println("makeDeclaration: declare = "+declare);
         StructuredBlock[] subs = getSubBlocks();
 	for (int i=0; i<subs.length; i++)
 	    subs[i].makeDeclaration(done);
         /* remove the variables again, since we leave the scope.
          */
-        done.subtractExact(declare);
+        done.removeAll(declare);
     }
 
     public void checkConsistent() {
@@ -569,7 +589,7 @@ public abstract class StructuredBlock {
      * dumpInstruction afterwards.
      * @param writer The tabbed print writer, where we print to.
      */
-    public void dumpSource(jode.decompiler.TabbedPrintWriter writer)
+    public void dumpSource(TabbedPrintWriter writer)
         throws java.io.IOException
     {
 	if ((GlobalOptions.debuggingFlags
@@ -584,8 +604,9 @@ public abstract class StructuredBlock {
 	if (declare != null) {
 	    java.util.Enumeration enum = declare.elements();
 	    while (enum.hasMoreElements()) {
-		LocalInfo local = (LocalInfo) enum.nextElement();
-		dumpDeclaration(writer, local);
+		Declarable decl = (Declarable) enum.nextElement();
+		decl.dumpDeclaration(writer);
+		writer.println(";");
 	    }
 	}
         dumpInstruction(writer);
@@ -594,20 +615,6 @@ public abstract class StructuredBlock {
             jump.dumpSource(writer);
     }
 
-    /**
-     * Print the code for the declaration of a local variable.
-     * @param writer The tabbed print writer, where we print to.
-     * @param local  The local that should be declared.
-     */
-    public void dumpDeclaration(jode.decompiler.TabbedPrintWriter writer, LocalInfo local)
-        throws java.io.IOException
-    {
-	if (!local.isRemoved()) {
-	    writer.printType(local.getType().getHint());
-	    writer.println(" " + local.getName().toString() + ";");
-	}
-    }
-
     /**
      * Print the instruction expressing this structured block.
      * @param writer The tabbed print writer, where we print to.
diff --git a/jode/jode/flow/SynchronizedBlock.java b/jode/jode/flow/SynchronizedBlock.java
index 3423abc..20c8bf2 100644
--- a/jode/jode/flow/SynchronizedBlock.java
+++ b/jode/jode/flow/SynchronizedBlock.java
@@ -21,6 +21,7 @@ package jode.flow;
 import jode.decompiler.LocalInfo;
 import jode.decompiler.TabbedPrintWriter;
 import jode.expr.Expression;
+import jode.util.SimpleSet;
 
 /**
  * This class represents a synchronized structured block.
@@ -70,12 +71,12 @@ public class SynchronizedBlock extends StructuredBlock {
         return true;
     }
 
-    public VariableSet getUsed() {
-	VariableSet used = new VariableSet();
+    public SimpleSet getDeclarables() {
+	SimpleSet used = new SimpleSet();
 	if (object != null)
-	    object.fillInGenSet(null, used);
+	    object.fillDeclarables(used);
 	else
-	    used.addElement(local);
+	    used.add(local);
 	return used;
     }
 
@@ -84,10 +85,12 @@ public class SynchronizedBlock extends StructuredBlock {
     {
         if (!isEntered)
             writer.println("MISSING MONITORENTER");
-        writer.print("synchronized ("
-		     + (object != null 
-			? object.toString()
-			: local.getName()) + ")");
+        writer.print("synchronized (");
+	if (object != null)
+	    object.dumpExpression(writer);
+	else
+	    writer.print(local.getName());
+	writer.print(")");
 	writer.openBrace();
         writer.tab();
         bodyBlock.dumpSource(writer);