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
IfStatement newIf = ast.newIfStatement();
				newIf.setExpression(condition);
				Statement bodyPlaceholder = (Statement) rewrite.createCopyTarget(innerIf.getThenStatement());
				newIf.setThenStatement(bodyPlaceholder);
				rewrite.replace(ifStatement, newIf, null);
				
				String label = CorrectionMessages.AdvancedQuickAssistProcessor_joinWithInner_description;
				Image image = JavaPluginImages.get(JavaPluginImages.IMG_CORRECTION_CHANGE);
				ASTRewriteCorrectionProposal proposal = new ASTRewriteCorrectionProposal(label,
						context.getCompilationUnit(), rewrite, 1, image);
				resultingCollections.add(proposal);
				result = true;
			}
		}
		return result;
	}
	private static Expression getParenthesizedForAndIfNeeded(AST ast, ASTRewrite rewrite, Expression expression) {
		boolean addParentheses = false;
		int nodeType = expression.getNodeType();
		if (nodeType == ASTNode.INFIX_EXPRESSION) {
			InfixExpression infixExpression = (InfixExpression) expression;
			addParentheses = infixExpression.getOperator() == InfixExpression.Operator.CONDITIONAL_OR;
		} else {
			addParentheses = nodeType == ASTNode.CONDITIONAL_EXPRESSION || nodeType == ASTNode.ASSIGNMENT
					|| nodeType == ASTNode.INSTANCEOF_EXPRESSION;
		}
		expression = (Expression) rewrite.createCopyTarget(expression);
		if (addParentheses) {
			return getParenthesizedExpression(ast, expression);
		}