/*
 * Copyright 2014 - 2020 Rafael Winterhalter
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package net.bytebuddy.implementation.bytecode;

import net.bytebuddy.description.type.TypeDefinition;
import net.bytebuddy.implementation.Implementation;
import org.objectweb.asm.MethodVisitor;
import org.objectweb.asm.Opcodes;

Removes a value from the operand stack.
/** * Removes a value from the operand stack. */
public enum Removal implements StackManipulation {
A removal of no value. This corresponds a no-op instruction.
/** * A removal of no value. This corresponds a no-op instruction. */
ZERO(StackSize.ZERO, Opcodes.NOP) {
{@inheritDoc}
/** {@inheritDoc} */
public Size apply(MethodVisitor methodVisitor, Implementation.Context implementationContext) { return new Size(0, 0); } },
A removal of a single-sized value.
/** * A removal of a single-sized value. */
SINGLE(StackSize.SINGLE, Opcodes.POP),
A removal of a double-sized value.
/** * A removal of a double-sized value. */
DOUBLE(StackSize.DOUBLE, Opcodes.POP2);
The size impact of the removal onto the operand stack.
/** * The size impact of the removal onto the operand stack. */
private final Size size;
The opcode to execute for the removal.
/** * The opcode to execute for the removal. */
private final int opcode;
Creates a new removal stack manipulation.
Params:
  • stackSize – The size impact of the removal onto the operand stack.
  • opcode – The opcode to execute for the removal.
/** * Creates a new removal stack manipulation. * * @param stackSize The size impact of the removal onto the operand stack. * @param opcode The opcode to execute for the removal. */
Removal(StackSize stackSize, int opcode) { size = stackSize.toDecreasingSize(); this.opcode = opcode; }
Removes a value from the operand stack dependant of its size.
Params:
  • typeDefinition – The type to remove from the stack.
Returns:A stack manipulation that represents the removal.
/** * Removes a value from the operand stack dependant of its size. * * @param typeDefinition The type to remove from the stack. * @return A stack manipulation that represents the removal. */
public static StackManipulation of(TypeDefinition typeDefinition) { switch (typeDefinition.getStackSize()) { case SINGLE: return SINGLE; case DOUBLE: return DOUBLE; case ZERO: return ZERO; default: throw new AssertionError(); } }
{@inheritDoc}
/** * {@inheritDoc} */
public boolean isValid() { return true; }
{@inheritDoc}
/** * {@inheritDoc} */
public Size apply(MethodVisitor methodVisitor, Implementation.Context implementationContext) { methodVisitor.visitInsn(opcode); return size; } }