// Copyright 2011 Howard M. Lewis Ship
//
// Licensed 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
//
// http://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.jplastic.internal;
import org.jplastic.core.InstructionBuilder;
import org.jplastic.core.InstructionBuilderCallback;
import org.jplastic.core.SwitchBlock;
import org.jplastic.core.SwitchCallback;
import org.objectweb.asm.Label;
import org.objectweb.asm.Opcodes;
public class SwitchBlockImpl extends Lockable implements SwitchBlock, Opcodes
{
private final InstructionBuilderState state;
private final int min, max;
private final Label defaultLabel, endSwitchLabel;
private final Label[] caseLabels;
private boolean defaultAdded = false;
SwitchBlockImpl(InstructionBuilderState state, int min, int max)
{
assert min <= max;
this.state = state;
this.min = min;
this.max = max;
defaultLabel = new Label();
endSwitchLabel = new Label();
caseLabels = new Label[max - min + 1];
for (int i = min; i <= max; i++)
{
caseLabels[i - min] = new Label();
}
state.visitor.visitTableSwitchInsn(min, max, defaultLabel, caseLabels);
}
void doCallback(SwitchCallback callback)
{
check();
callback.doSwitch(this);
if (!defaultAdded)
{
addDefault(new InstructionBuilderCallback()
{
public void doBuild(InstructionBuilder builder)
{
builder.throwException(IllegalArgumentException.class,
"Switch value not matched in case statement.");
}
});
}
state.visitor.visitLabel(endSwitchLabel);
lock();
}
public void addCase(int caseValue, boolean jumpToEnd, InstructionBuilderCallback callback)
{
assert caseValue >= min;
assert caseValue <= max;
if (defaultAdded)
throw new IllegalStateException("The default block must come last.");
// TODO: Check that no case value is repeated
state.visitor.visitLabel(caseLabels[caseValue - min]);
new InstructionBuilderImpl(state).doCallback(callback);
if (jumpToEnd)
state.visitor.visitJumpInsn(GOTO, endSwitchLabel);
}
public void addDefault(InstructionBuilderCallback callback)
{
if (defaultAdded)
throw new IllegalStateException("A SwitchBlock may only have one default block.");
state.visitor.visitLabel(defaultLabel);
new InstructionBuilderImpl(state).doCallback(callback);
defaultAdded = true;
}
}