/**
*
* Copyright (c) 2014, the Railo Company Ltd. All rights reserved.
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library. If not, see <http://www.gnu.org/licenses/>.
*
**/
package lucee.transformer.bytecode.expression;
import lucee.transformer.TransformerException;
import lucee.transformer.bytecode.BytecodeContext;
import lucee.transformer.bytecode.util.Types;
import lucee.transformer.expression.Expression;
import org.objectweb.asm.Label;
import org.objectweb.asm.Opcodes;
import org.objectweb.asm.Type;
import org.objectweb.asm.commons.GeneratorAdapter;
public class FailSafeExpression extends ExpressionBase implements Opcodes {
private Expression expr;
private Expression defaultValue;
public FailSafeExpression(Expression expr,Expression defaultValue) {
super(expr.getFactory(),expr.getStart(), expr.getEnd());
this.expr=expr;
this.defaultValue=defaultValue;
}
@Override
public Type _writeOut(BytecodeContext bc, int mode) throws TransformerException {
GeneratorAdapter mv = bc.getAdapter();
int local = mv.newLocal(Types.OBJECT);
{
Label begin = new Label();
Label onSuccess = new Label();
Label onFail = new Label();
Label end = new Label();
mv.visitTryCatchBlock(begin, onSuccess, onFail, "java/lang/Throwable");
mv.visitLabel(begin);
expr.writeOut(bc, MODE_REF);
mv.storeLocal(local);
mv.visitLabel(onSuccess);
mv.visitJumpInsn(GOTO, end);
mv.visitLabel(onFail);
//mv.visitVarInsn(ASTORE, 2);
defaultValue.writeOut(bc, MODE_REF);
mv.storeLocal(local);
mv.visitLabel(end);
mv.loadLocal(local);
//mv.visitLocalVariable("e", "Ljava/lang/Throwable;", null, l4, l3, 3);
}
return Types.OBJECT;
}
}