1 /*
   2  * Copyright (c) 2017, 2020, Oracle and/or its affiliates. All rights reserved.
   3  */
   4 /*
   5  * Licensed to the Apache Software Foundation (ASF) under one or more
   6  * contributor license agreements.  See the NOTICE file distributed with
   7  * this work for additional information regarding copyright ownership.
   8  * The ASF licenses this file to You under the Apache License, Version 2.0
   9  * (the "License"); you may not use this file except in compliance with
  10  * the License.  You may obtain a copy of the License at
  11  *
  12  *      http://www.apache.org/licenses/LICENSE-2.0
  13  *
  14  * Unless required by applicable law or agreed to in writing, software
  15  * distributed under the License is distributed on an "AS IS" BASIS,
  16  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  17  * See the License for the specific language governing permissions and
  18  * limitations under the License.
  19  */
  20 
  21 package com.sun.org.apache.bcel.internal.generic;
  22 
  23 import com.sun.org.apache.bcel.internal.Const;
  24 import com.sun.org.apache.bcel.internal.ExceptionConst;
  25 
  26 /**
  27  * Super class for the xRETURN family of instructions.
  28  *
  29  * @LastModified: Jan 2020
  30  */
  31 public abstract class ReturnInstruction extends Instruction implements ExceptionThrower,
  32         TypedInstruction, StackConsumer {
  33 
  34     /**
  35      * Empty constructor needed for Instruction.readInstruction.
  36      * Not to be used otherwise.
  37      */
  38     ReturnInstruction() {
  39     }
  40 
  41 
  42     /**
  43      * @param opcode of instruction
  44      */
  45     protected ReturnInstruction(final short opcode) {
  46         super(opcode, (short) 1);
  47     }
  48 
  49 
  50     public Type getType() {
  51         final short _opcode = super.getOpcode();
  52         switch (_opcode) {
  53             case Const.IRETURN:
  54                 return Type.INT;
  55             case Const.LRETURN:
  56                 return Type.LONG;
  57             case Const.FRETURN:
  58                 return Type.FLOAT;
  59             case Const.DRETURN:
  60                 return Type.DOUBLE;
  61             case Const.ARETURN:
  62                 return Type.OBJECT;
  63             case Const.RETURN:
  64                 return Type.VOID;
  65             default: // Never reached
  66                 throw new ClassGenException("Unknown type " + _opcode);
  67         }
  68     }
  69 
  70 
  71     @Override
  72     public Class<?>[] getExceptions() {
  73         return new Class<?>[] {
  74             ExceptionConst.ILLEGAL_MONITOR_STATE
  75         };
  76     }
  77 
  78 
  79     /** @return type associated with the instruction
  80      */
  81     @Override
  82     public Type getType( final ConstantPoolGen cp ) {
  83         return getType();
  84     }
  85 }