ExceptionHandlingFlowContext: use java.util.IdentityHashMap

* avoids raw types
* deletes custom ObjectCache

ObjectCache implemented a HashMap using hashCode() but not equals().
Instead it used == identity. JDK offers a special Map for identity since
1.4, consistently using System.identityHashCode().

relates to eclipse-jdt#3412

org.eclipse.jdt.core.compiler.batch/src/org/eclipse/jdt/internal/compiler/flow/ExceptionHandlingFlowContext.java

@@ -20,6 +20,7 @@
 
 import java.util.ArrayList;
 import java.util.Arrays;
+import java.util.IdentityHashMap;
 import java.util.List;
 import org.eclipse.jdt.internal.compiler.ast.ASTNode;
 import org.eclipse.jdt.internal.compiler.ast.AbstractMethodDeclaration;
@@ -28,7 +29,6 @@
 import org.eclipse.jdt.internal.compiler.ast.TryStatement;
 import org.eclipse.jdt.internal.compiler.ast.TypeReference;
 import org.eclipse.jdt.internal.compiler.ast.UnionTypeReference;
-import org.eclipse.jdt.internal.compiler.codegen.ObjectCache;
 import org.eclipse.jdt.internal.compiler.lookup.BlockScope;
 import org.eclipse.jdt.internal.compiler.lookup.CatchParameterBinding;
 import org.eclipse.jdt.internal.compiler.lookup.ExtraCompilerModifiers;
@@ -42,7 +42,6 @@
  * Reflects the context of code analysis, keeping track of enclosing
  *	try statements, exception handlers, etc...
  */
-@SuppressWarnings({"rawtypes", "unchecked"})
 public class ExceptionHandlingFlowContext extends FlowContext {
 
 	public final static int BitCacheSize = 32; // 32 bits per int
@@ -52,14 +51,14 @@ public class ExceptionHandlingFlowContext extends FlowContext {
 	int[] isNeeded;
 	// WARNING: This is an array that maps to catch blocks, not caught exceptions (which could be more than catch blocks in a multi-catch block)
 	UnconditionalFlowInfo[] initsOnExceptions;
-	ObjectCache indexes = new ObjectCache();
+	IdentityHashMap<ReferenceBinding, Integer> indexes = new IdentityHashMap<>();
 	boolean isMethodContext;
 
 	public UnconditionalFlowInfo initsOnReturn;
 	public FlowContext initializationParent; // special parent relationship only for initialization purpose
 
 	// for dealing with anonymous constructor thrown exceptions
-	public List extendedExceptions;
+	public List<TypeBinding> extendedExceptions;
 
 	private static final Argument[] NO_ARGUMENTS = new Argument[0];
 	public  Argument [] catchArguments;
@@ -255,7 +254,7 @@ public void mergeUnhandledException(TypeBinding newException){
 	boolean isRedundant = false;
 
 	for(int i = this.extendedExceptions.size()-1; i >= 0; i--){
-		switch(Scope.compareTypes(newException, (TypeBinding)this.extendedExceptions.get(i))){
+		switch(Scope.compareTypes(newException, this.extendedExceptions.get(i))){
 			case Scope.MORE_GENERIC :
 				this.extendedExceptions.remove(i);
 				break;