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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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 *
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 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
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package org.graalvm.compiler.bytecode;

A utility for processing Bytecodes.TABLESWITCH bytecodes. /**
 * A utility for processing {@link Bytecodes#TABLESWITCH} bytecodes.
 */
public class BytecodeTableSwitch extends BytecodeSwitch {

    private static final int OFFSET_TO_LOW_KEY = 4;
    private static final int OFFSET_TO_HIGH_KEY = 8;
    private static final int OFFSET_TO_FIRST_JUMP_OFFSET = 12;
    private static final int JUMP_OFFSET_SIZE = 4;

    
Constructor for a BytecodeStream. 
Params:
stream – the BytecodeStream containing the switch instruction
bci – the index in the stream of the switch instruction/**
     * Constructor for a {@link BytecodeStream}.
     *
     * @param stream the {@code BytecodeStream} containing the switch instruction
     * @param bci the index in the stream of the switch instruction
     */
    public BytecodeTableSwitch(BytecodeStream stream, int bci) {
        super(stream, bci);
    }

    
Gets the low key of the table switch.
Returns:
the low key/**
     * Gets the low key of the table switch.
     *
     * @return the low key
     */
    public int lowKey() {
        return stream.readInt(alignedBci + OFFSET_TO_LOW_KEY);
    }

    
Gets the high key of the table switch.
Returns:
the high key/**
     * Gets the high key of the table switch.
     *
     * @return the high key
     */
    public int highKey() {
        return stream.readInt(alignedBci + OFFSET_TO_HIGH_KEY);
    }

    @Override
    public int keyAt(int i) {
        return lowKey() + i;
    }

    @Override
    public int offsetAt(int i) {
        return stream.readInt(alignedBci + OFFSET_TO_FIRST_JUMP_OFFSET + JUMP_OFFSET_SIZE * i);
    }

    @Override
    public int numberOfCases() {
        return highKey() - lowKey() + 1;
    }

    @Override
    public int size() {
        return alignedBci + OFFSET_TO_FIRST_JUMP_OFFSET + JUMP_OFFSET_SIZE * numberOfCases() - bci;
    }
}