Bugfix for object finalization in Java API.

Relates to #205 and #245

src/api/java/AST.java

@@ -33,7 +33,7 @@ public class AST extends Z3Object implements Comparable
     {
         AST casted = null;
 
-	try
+        try
         {
             casted = AST.class.cast(o);
         } catch (ClassCastException e)
@@ -41,13 +41,12 @@ public class AST extends Z3Object implements Comparable
             return false;
         }
 
-	return  
+        return  (this == casted) ||
-	    (this == casted) || 
+                (this != null) &&
-	    (this != null) &&
+                (casted != null) &&
-	    (casted != null) &&
+                (getContext().nCtx() == casted.getContext().nCtx()) &&
-	    (getContext().nCtx() == casted.getContext().nCtx()) &&
+                (Native.isEqAst(getContext().nCtx(), getNativeObject(), casted.getNativeObject()));
-	    (Native.isEqAst(getContext().nCtx(), getNativeObject(), casted.getNativeObject()));
+    }
-}
 
     /**
      * Object Comparison. 

src/api/java/Constructor.java

@@ -80,11 +80,20 @@ public class Constructor extends Z3Object
 
     /**
      * Destructor.
+     * @throws Throwable 
      * @throws Z3Exception on error
      **/
-    protected void finalize()
+    protected void finalize() throws Throwable
     {
-        Native.delConstructor(getContext().nCtx(), getNativeObject());
+        try {
+            Native.delConstructor(getContext().nCtx(), getNativeObject());
+        }
+        catch (Throwable t) {
+            throw t;
+        }
+        finally {
+            super.finalize();
+        }
     }
 
     private int n = 0;

src/api/java/ConstructorList.java

@@ -24,11 +24,20 @@ public class ConstructorList extends Z3Object
 {
     /**
      * Destructor.
+     * @throws Throwable 
      * @throws Z3Exception on error
      **/
-    protected void finalize()
+    protected void finalize() throws Throwable
     {
-        Native.delConstructorList(getContext().nCtx(), getNativeObject());
+        try {        
+            Native.delConstructorList(getContext().nCtx(), getNativeObject());            
+        }
+        catch (Throwable t) {
+            throw t;
+        }
+        finally {
+            super.finalize();
+        }
     }
 
     ConstructorList(Context ctx, long obj)

src/api/java/Z3Object.java

@@ -25,10 +25,19 @@ public class Z3Object extends IDisposable
 {
     /**
      * Finalizer.
+     * @throws Throwable 
      **/
-    protected void finalize()
+    protected void finalize() throws Throwable
     {
-        dispose();
+        try {
+            dispose();            
+        }
+        catch (Throwable t) {
+            throw t;
+        }
+        finally {
+            super.finalize();
+        }
     }
 
     /**