org.datanucleus.enhancer.asm.method.JdoProvideField Maven / Gradle / Ivy
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DataNucleus Enhancer is a Java byte-code enhancer for use with DataNucleus.
/**********************************************************************
Copyright (c) 2007 Andy Jefferson and others. All rights reserved.
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.
Contributors:
...
**********************************************************************/
package org.datanucleus.enhancer.asm.method;
import org.datanucleus.enhancer.ClassEnhancer;
import org.datanucleus.enhancer.asm.ASMClassMethod;
import org.datanucleus.enhancer.asm.ASMUtils;
import org.datanucleus.metadata.AbstractMemberMetaData;
import org.datanucleus.metadata.PropertyMetaData;
import org.objectweb.asm.Label;
import org.objectweb.asm.Opcodes;
import org.objectweb.asm.Type;
/**
* Method to generate the method "jdoProvideField" using ASM.
*
* public void jdoProvideField(int fieldIndex)
* {
* if (jdoStateManager == null)
* throw new IllegalStateException("state manager is null");
* switch (fieldIndex)
* {
* case 0:
* jdoStateManager.providedObjectField(this, fieldIndex, question);
* break;
* default:
* throw new IllegalArgumentException("out of field index :" + fieldIndex);
* }
* }
*
* and with a superclass
*
* public void jdoProvideField(int fieldIndex)
* {
* if (jdoStateManager == null)
* throw new IllegalStateException("state manager is null");
* switch (fieldIndex - jdoInheritedFieldCount)
* {
* case 0:
* jdoStateManager.providedStringField(this, fieldIndex, extraInfo);
* break;
* default:
* super.jdoProvideField(fieldIndex);
* }
* }
*
* with further minor changes when the class has no fields.
*/
public class JdoProvideField extends ASMClassMethod
{
public static JdoProvideField getInstance(ClassEnhancer enhancer)
{
return new JdoProvideField(enhancer, enhancer.getProvideFieldMethodName(), Opcodes.ACC_PUBLIC,
null, new Class[] {int.class}, new String[] {"index"});
}
/**
* Constructor.
* @param enhancer ClassEnhancer
* @param name Name of method
* @param access Access type
* @param returnType Return type
* @param argTypes Argument types
* @param argNames Argument names
*/
public JdoProvideField(ClassEnhancer enhancer, String name, int access,
Object returnType, Object[] argTypes, String[] argNames)
{
super(enhancer, name, access, returnType, argTypes, argNames);
}
/**
* Method to add the contents of the class method.
*/
public void execute()
{
AbstractMemberMetaData fields[] = enhancer.getClassMetaData().getManagedMembers();
String pcSuperclassName = enhancer.getClassMetaData().getPersistenceCapableSuperclass();
visitor.visitCode();
Label startLabel = new Label();
visitor.visitLabel(startLabel);
if (pcSuperclassName != null)
{
if (fields.length > 0)
{
visitor.visitVarInsn(Opcodes.ALOAD, 0);
visitor.visitFieldInsn(Opcodes.GETFIELD, getClassEnhancer().getASMClassName(),
enhancer.getStateManagerFieldName(), enhancer.getStateManagerDescriptor());
Label l1 = new Label();
visitor.visitJumpInsn(Opcodes.IFNONNULL, l1);
visitor.visitTypeInsn(Opcodes.NEW, "java/lang/IllegalStateException");
visitor.visitInsn(Opcodes.DUP);
visitor.visitLdcInsn("state manager is null");
visitor.visitMethodInsn(Opcodes.INVOKESPECIAL, "java/lang/IllegalStateException",
"", "(Ljava/lang/String;)V");
visitor.visitInsn(Opcodes.ATHROW);
visitor.visitLabel(l1);
visitor.visitVarInsn(Opcodes.ILOAD, 1);
visitor.visitFieldInsn(Opcodes.GETSTATIC, getClassEnhancer().getASMClassName(),
enhancer.getInheritedFieldCountFieldName(), "I");
visitor.visitInsn(Opcodes.ISUB);
Label[] fieldOptions = new Label[fields.length];
for (int i=0;i 0)
{
visitor.visitVarInsn(Opcodes.ALOAD, 0);
visitor.visitFieldInsn(Opcodes.GETFIELD, getClassEnhancer().getASMClassName(),
enhancer.getStateManagerFieldName(), enhancer.getStateManagerDescriptor());
Label l1 = new Label();
visitor.visitJumpInsn(Opcodes.IFNONNULL, l1);
visitor.visitTypeInsn(Opcodes.NEW, "java/lang/IllegalStateException");
visitor.visitInsn(Opcodes.DUP);
visitor.visitLdcInsn("state manager is null");
visitor.visitMethodInsn(Opcodes.INVOKESPECIAL, "java/lang/IllegalStateException",
"", "(" + ASMUtils.CD_String + ")V");
visitor.visitInsn(Opcodes.ATHROW);
visitor.visitLabel(l1);
visitor.visitVarInsn(Opcodes.ILOAD, 1);
Label[] fieldOptions = new Label[fields.length];
for (int i=0;i", "(Ljava/lang/String;)V");
visitor.visitVarInsn(Opcodes.ILOAD, 1);
visitor.visitMethodInsn(Opcodes.INVOKEVIRTUAL, "java/lang/StringBuffer", "append", "(I)Ljava/lang/StringBuffer;");
visitor.visitMethodInsn(Opcodes.INVOKEVIRTUAL, "java/lang/StringBuffer", "toString", "()Ljava/lang/String;");
visitor.visitMethodInsn(Opcodes.INVOKESPECIAL, "java/lang/IllegalArgumentException", "", "(Ljava/lang/String;)V");
visitor.visitInsn(Opcodes.ATHROW);
// End of switch
visitor.visitLabel(endSwitchLabel);
visitor.visitInsn(Opcodes.RETURN);
Label l7 = new Label();
visitor.visitLabel(l7);
visitor.visitLocalVariable("this", getClassEnhancer().getClassDescriptor(), null, startLabel, l7, 0);
visitor.visitLocalVariable(argNames[0], "I", null, startLabel, l7, 1);
visitor.visitMaxs(5, 2);
}
else
{
visitor.visitInsn(Opcodes.RETURN);
Label endLabel = new Label();
visitor.visitLabel(endLabel);
visitor.visitLocalVariable("this", getClassEnhancer().getClassDescriptor(), null, startLabel, endLabel, 0);
visitor.visitLocalVariable(argNames[0], "I", null, startLabel, endLabel, 1);
visitor.visitMaxs(0, 2);
}
}
visitor.visitEnd();
}
}