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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(); }