Bug 120389 [quick fix] replace conditional with if-else removes + from +=
Using Build I20051102-1600. I create a class [snip] package bla; class Bla { void bla() { boolean cond = true; int i = 42; i += ( cond ) ? 1 : 2; } } [snap] Now I move the cursor over the second cond and trigger the Quickfix 'Replace conditional with if-else'. This results in [snip] int i = 42; if (cond) i = 1; else i = 2; [snap] i.e. replaces the '+=' with '='. (Credit to Jordi Boehme for finding this.)
org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/text/correction/AdvancedQuickAssistProcessor.java
final String notString = Messages.format(CorrectionMessages.AdvancedQuickAssistProcessor_negatedVariableName, "");  
		final String newIdentifier;
		if (oldIdentifier.startsWith(notString)) {
			int notLength= notString.length();
			if (oldIdentifier.length() > notLength) {
				newIdentifier= Character.toLowerCase(oldIdentifier.charAt(notLength)) + oldIdentifier.substring(notLength + 1);
			} else {
				newIdentifier= oldIdentifier;
			}
		} else {
			newIdentifier= Messages.format(CorrectionMessages.AdvancedQuickAssistProcessor_negatedVariableName, Character.toUpperCase(oldIdentifier.charAt(0)) + oldIdentifier.substring(1));
		}
		
		proposal.addLinkedPositionProposal(KEY_NAME, newIdentifier, null);
		proposal.addLinkedPositionProposal(KEY_NAME, oldIdentifier, null);
		
		final HashSet renamedNames= new HashSet();
		for (int i= 0; i < linkedNodes.length; i++) {
			SimpleName name= linkedNodes[i];
			if (renamedNames.contains(name)) {
				continue;
			}
			
			SimpleName newName= ast.newSimpleName(newIdentifier);
			proposal.addLinkedPosition(rewrite.track(newName), name == coveringName, KEY_NAME);
			
			StructuralPropertyDescriptor location= name.getLocationInParent();
			if (location == SingleVariableDeclaration.NAME_PROPERTY) {
				
				rewrite.replace(name, newName, null);