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package org.graalvm.compiler.bytecode;

An abstract class that provides the state and methods common to Bytecodes.LOOKUPSWITCH and Bytecodes.TABLESWITCH instructions. /**
 * An abstract class that provides the state and methods common to {@link Bytecodes#LOOKUPSWITCH}
 * and {@link Bytecodes#TABLESWITCH} instructions.
 */
public abstract class BytecodeSwitch {

    
The BytecodeStream containing the bytecode array. /**
     * The {@link BytecodeStream} containing the bytecode array.
     */
    protected final BytecodeStream stream;
    
Index of start of switch instruction.
/**
     * Index of start of switch instruction.
     */
    protected final int bci;
    
Index of the start of the additional data for the switch instruction, aligned to a multiple
of four from the method start.
/**
     * Index of the start of the additional data for the switch instruction, aligned to a multiple
     * of four from the method start.
     */
    protected final int alignedBci;

    
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 BytecodeSwitch(BytecodeStream stream, int bci) {
        this.stream = stream;
        this.bci = bci;
        this.alignedBci = (bci + 4) & 0xfffffffc;
    }

    
Gets the current bytecode index.
Returns:
the current bytecode index/**
     * Gets the current bytecode index.
     *
     * @return the current bytecode index
     */
    public int bci() {
        return bci;
    }

    
Gets the index of the instruction denoted by the i'th switch target. 
Params:
i – index of the switch target
Returns:
the index of the instruction denoted by the i'th switch target/**
     * Gets the index of the instruction denoted by the {@code i}'th switch target.
     *
     * @param i index of the switch target
     * @return the index of the instruction denoted by the {@code i}'th switch target
     */
    public int targetAt(int i) {
        return bci + offsetAt(i);
    }

    
Gets the index of the instruction for the default switch target.
Returns:
the index of the instruction for the default switch target/**
     * Gets the index of the instruction for the default switch target.
     *
     * @return the index of the instruction for the default switch target
     */
    public int defaultTarget() {
        return bci + defaultOffset();
    }

    
Gets the offset from the start of the switch instruction to the default switch target.
Returns:
the offset to the default switch target/**
     * Gets the offset from the start of the switch instruction to the default switch target.
     *
     * @return the offset to the default switch target
     */
    public int defaultOffset() {
        return stream.readInt(alignedBci);
    }

    
Gets the key at i'th switch target index. 
Params:
i – the switch target index
Returns:
the key at i'th switch target index/**
     * Gets the key at {@code i}'th switch target index.
     *
     * @param i the switch target index
     * @return the key at {@code i}'th switch target index
     */
    public abstract int keyAt(int i);

    
Gets the offset from the start of the switch instruction for the i'th switch target. 
Params:
i – the switch target index
Returns:
the offset to the i'th switch target/**
     * Gets the offset from the start of the switch instruction for the {@code i}'th switch target.
     *
     * @param i the switch target index
     * @return the offset to the {@code i}'th switch target
     */
    public abstract int offsetAt(int i);

    
Gets the number of switch targets.
Returns:
the number of switch targets/**
     * Gets the number of switch targets.
     *
     * @return the number of switch targets
     */
    public abstract int numberOfCases();

    
Gets the total size in bytes of the switch instruction.
Returns:
the total size in bytes of the switch instruction/**
     * Gets the total size in bytes of the switch instruction.
     *
     * @return the total size in bytes of the switch instruction
     */
    public abstract int size();

}