/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you 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
 *
 *   https://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 org.apache.bcel.generic;

import org.apache.bcel.ExceptionConst;

/**
 * Super class for instructions dealing with array access such as IALOAD.
 */
public abstract class ArrayInstruction extends Instruction implements ExceptionThrower, TypedInstruction {

    /**
     * Empty constructor needed for Instruction.readInstruction. Not to be used otherwise.
     */
    ArrayInstruction() {
    }

    /**
     * Constructs an ArrayInstruction.
     *
     * @param opcode of instruction.
     */
    protected ArrayInstruction(final short opcode) {
        super(opcode, (short) 1);
    }

    @Override
    public Class<?>[] getExceptions() {
        return ExceptionConst.createExceptions(ExceptionConst.EXCS.EXCS_ARRAY_EXCEPTION);
    }

    /**
     * @return type associated with the instruction.
     */
    @Override
    public Type getType(final ConstantPoolGen cp) {
        final short opcode = super.getOpcode();
        switch (opcode) {
        case org.apache.bcel.Const.IALOAD:
        case org.apache.bcel.Const.IASTORE:
            return Type.INT;
        case org.apache.bcel.Const.CALOAD:
        case org.apache.bcel.Const.CASTORE:
            return Type.CHAR;
        case org.apache.bcel.Const.BALOAD:
        case org.apache.bcel.Const.BASTORE:
            return Type.BYTE;
        case org.apache.bcel.Const.SALOAD:
        case org.apache.bcel.Const.SASTORE:
            return Type.SHORT;
        case org.apache.bcel.Const.LALOAD:
        case org.apache.bcel.Const.LASTORE:
            return Type.LONG;
        case org.apache.bcel.Const.DALOAD:
        case org.apache.bcel.Const.DASTORE:
            return Type.DOUBLE;
        case org.apache.bcel.Const.FALOAD:
        case org.apache.bcel.Const.FASTORE:
            return Type.FLOAT;
        case org.apache.bcel.Const.AALOAD:
        case org.apache.bcel.Const.AASTORE:
            return Type.OBJECT;
        default:
            throw new ClassGenException("Unknown case in switch" + opcode);
        }
    }
}
