AbsOperator.java

package com.hubspot.jinjava.el.ext;

import de.odysseus.el.misc.TypeConverter;
import de.odysseus.el.tree.impl.Parser.ExtensionHandler;
import de.odysseus.el.tree.impl.Parser.ExtensionPoint;
import de.odysseus.el.tree.impl.Scanner;
import de.odysseus.el.tree.impl.Scanner.ExtensionToken;
import de.odysseus.el.tree.impl.ast.AstNode;
import de.odysseus.el.tree.impl.ast.AstUnary;

public class AbsOperator {

  public static final ExtensionToken TOKEN = new Scanner.ExtensionToken("+");

  public static final ExtensionHandler HANDLER = new ExtensionHandler(ExtensionPoint.UNARY) {
    @Override
    public AstNode createAstNode(AstNode... children) {
      return new AstUnary(children[0], new AstUnary.SimpleOperator() {
        @Override
        protected Object apply(TypeConverter converter, Object o) {
          if (o == null) {
            return null;
          }

          if (o instanceof Float) {
            return Math.abs((Float) o);
          }
          if (o instanceof Double) {
            return Math.abs((Double) o);
          }
          if (o instanceof Integer) {
            return Math.abs((Integer) o);
          }
          if (o instanceof Long) {
            return Math.abs((Long) o);
          }

          throw new IllegalArgumentException("Unable to apply abs operator on object of type: " + o.getClass());
        }
      });
    }
  };

}