Get from Expression Left, Operator and Right and Save into list

[rider87]

Hi,

I saw I can get from a Expression the left, operator and right side...
I would like to extract that into a List to do something else later on...

What I´m trying to do is to get the whole Expression:

• Convert this expression into Java Code
• Validate this against Java...
• E.g. you have Expression 1==1... I would like to check this directly in Java if(1==1) e.g

` private static String test(BinaryExpression expr) {

	boolean test; 

	ExpressionVisitorAdapter expressionVisitorAdapter = new ExpressionVisitorAdapter();

	expr.accept(new ExpressionVisitorAdapter() {
		protected void visitBinaryExpression(BinaryExpression expr) {
			if (expr instanceof ComparisonOperator) {

				Object left = expr.getLeftExpression();
				Object operator = expr.getLeftExpression();
				Object right = expr.getLeftExpression();

				System.out.println("left=" + expr.getLeftExpression() + "  op=" + expr.getStringExpression()
						+ "  right=" + expr.getRightExpression());
			}
						
			super.visitBinaryExpression(expr);
		}
	});
	
	return expr.getLeftExpression().toString();
}`

Is there a possibility to get this? Due tot he fact it´s procted I cannot add a List<> from outside the :
expr.accept(new ExpressionVisitorAdapter() {

Any ideas?

[manticore-projects]

Greetings.

You can define a final list outside of the accept and add elements to this list inside the visit method.
However, I struggle to understand what you would like to achieve as we are not talking about a list but rather about a tree of nested expressions.

[manticore-projects]

private static String test(BinaryExpression expr) {

    boolean test;
    final ArrayList<Expression> expressions = new ArrayList<>();
    
    ExpressionVisitorAdapter expressionVisitorAdapter = new ExpressionVisitorAdapter();

    expr.accept(new ExpressionVisitorAdapter() {
      protected void visitBinaryExpression(BinaryExpression expr) {
        if (expr instanceof ComparisonOperator) {
            ComparisonOperator comparisonOperator = (ComparisonOperator) expr;

         Expression leftExpression = comparisonOperator.getLeftExpression();
         String operator = comparisonOperator.getStringExpression();
         Expression rightExpression =  comparisonOperator.getRightExpression();

         System.out.println("left=" + leftExpression + "  op="
              + operator + "  right=" + rightExpression);
         
         expressions.add(leftExpression);
         expressions.add(rightExpression);
        }

        super.visitBinaryExpression(expr);
      }
    });
    
    StringBuilder builder = new StringBuilder();
    for (Expression expression:expressions)
        builder.append(expression.toString());
    
    return builder.toString();
  }