### Eclipse Workspace Patch 1.0
#P org.eclipse.jdt.core
Index: codeassist/org/eclipse/jdt/internal/codeassist/InternalCompletionProposal.java
===================================================================
RCS file: /cvsroot/eclipse/org.eclipse.jdt.core/codeassist/org/eclipse/jdt/internal/codeassist/InternalCompletionProposal.java,v
retrieving revision 1.14
diff -u -r1.14 InternalCompletionProposal.java
--- codeassist/org/eclipse/jdt/internal/codeassist/InternalCompletionProposal.java	22 Jan 2009 09:46:59 -0000	1.14
+++ codeassist/org/eclipse/jdt/internal/codeassist/InternalCompletionProposal.java	28 Jun 2010 11:10:33 -0000
@@ -210,11 +210,10 @@
 		}
 
 		if(type != null) {
-			String[] args = new String[length];
-			for(int i = 0;	i< length ; i++){
-				args[i] = new String(paramTypeNames[i]);
-			}
-			IMethod method = type.getMethod(new String(selector),args);
+			// https://bugs.eclipse.org/bugs/show_bug.cgi?id=316937
+			// BinaryType#getMethod() creates a new instance of BinaryMethod, which is a dummy.
+			// Instead we have to use IType#findMethods() to get a handle to the method of our interest.
+			IMethod method = findMethod(type, selector, paramTypeNames);
 			
 			if (this.hasNoParameterNamesFromIndex) {
 				IPackageFragmentRoot packageFragmentRoot = (IPackageFragmentRoot)type.getAncestor(IJavaElement.PACKAGE_FRAGMENT_ROOT);
@@ -307,11 +306,10 @@
 		}
 
 		if(type != null) {
-			String[] args = new String[length];
-			for(int i = 0;	i< length ; i++){
-				args[i] = new String(paramTypeNames[i]);
-			}
-			IMethod method = type.getMethod(new String(selector),args);
+			// https://bugs.eclipse.org/bugs/show_bug.cgi?id=316937
+			// BinaryType#getMethod() creates a new instance of BinaryMethod, which is a dummy.
+			// Instead we have to use IType#findMethods() to get a handle to the method of our interest.
+			IMethod method = findMethod(type, selector, paramTypeNames);
 			try{
 				parameters = new char[length][];
 				String[] params = method.getParameterNames();
@@ -331,6 +329,34 @@
 		return parameters;
 	}
 
+	private IMethod findMethod(IType type, char[] selector, char[][] paramTypeNames) {
+		IMethod method = null;
+		int startingIndex = 0;
+		String[] args;
+		IType enclosingType = type.getDeclaringType();
+		// If the method is a constructor of an inner type, add the enclosing type as an 
+		// additional parameter to the constructor.
+		if (enclosingType != null && CharOperation.equals(type.getElementName().toCharArray(), selector)) {
+			args = new String[paramTypeNames.length+1];
+			startingIndex = 1;
+			args[0] = Signature.createTypeSignature(enclosingType.getFullyQualifiedName(), true);
+		}
+		else {
+			args = new String[paramTypeNames.length];
+		}
+		int length = args.length;
+		for(int i = startingIndex;	i< length ; i++){
+			args[i] = new String(paramTypeNames[i-startingIndex]);
+		}
+		method = type.getMethod(new String(selector), args);
+		
+		IMethod[] methods = type.findMethods(method);
+		if (methods != null && methods.length > 0) {
+			method = methods[0];
+		}
+		return method;
+	}
+
 	protected char[] getDeclarationPackageName() {
 		return this.declarationPackageName;
 	}
Index: model/org/eclipse/jdt/internal/core/BinaryMethod.java
===================================================================
RCS file: /cvsroot/eclipse/org.eclipse.jdt.core/model/org/eclipse/jdt/internal/core/BinaryMethod.java,v
retrieving revision 1.105
diff -u -r1.105 BinaryMethod.java
--- model/org/eclipse/jdt/internal/core/BinaryMethod.java	7 Mar 2009 00:58:57 -0000	1.105
+++ model/org/eclipse/jdt/internal/core/BinaryMethod.java	28 Jun 2010 11:10:34 -0000
@@ -181,7 +181,10 @@
 
 	// try to see if we can retrieve the names from the attached javadoc
 	IBinaryMethod info = (IBinaryMethod) getElementInfo();
-	final int paramCount = Signature.getParameterCount(new String(info.getMethodDescriptor()));
+	// https://bugs.eclipse.org/bugs/show_bug.cgi?id=316937
+	// Use Signature#getParameterCount() only if the argument names are not already available.
+	final int paramCount = info.getArgumentNames() == null ? info.getArgumentNames().length : 
+										Signature.getParameterCount(new String(info.getMethodDescriptor()));
 	if (paramCount != 0) {
 		// don't try to look for javadoc for synthetic methods
 		int modifiers = getFlags();