/*******************************************************************************
* Copyright (c) 1998, 2010 Oracle. All rights reserved.
* This program and the accompanying materials are made available under the
* terms of the Eclipse Public License v1.0 and Eclipse Distribution License v. 1.0
* which accompanies this distribution.
* The Eclipse Public License is available at http://www.eclipse.org/legal/epl-v10.html
* and the Eclipse Distribution License is available at
* http://www.eclipse.org/org/documents/edl-v10.php.
*
* Contributors:
* mnorman - convert DBWS to use new EclipseLink public Dynamic Persistence APIs
******************************************************************************/
package org.eclipse.persistence.internal.xr;
//javase imports
//EclipseLink imports
import org.eclipse.persistence.dynamic.DynamicClassLoader;
import org.eclipse.persistence.dynamic.DynamicClassWriter;
import org.eclipse.persistence.internal.libraries.asm.ClassWriter;
import org.eclipse.persistence.internal.libraries.asm.CodeVisitor;
import org.eclipse.persistence.internal.xr.XRFieldInfo;
import static org.eclipse.persistence.internal.libraries.asm.Constants.ACC_PUBLIC;
import static org.eclipse.persistence.internal.libraries.asm.Constants.ACC_STATIC;
import static org.eclipse.persistence.internal.libraries.asm.Constants.ACC_SUPER;
import static org.eclipse.persistence.internal.libraries.asm.Constants.ALOAD;
import static org.eclipse.persistence.internal.libraries.asm.Constants.ARETURN;
import static org.eclipse.persistence.internal.libraries.asm.Constants.DUP;
import static org.eclipse.persistence.internal.libraries.asm.Constants.GETSTATIC;
import static org.eclipse.persistence.internal.libraries.asm.Constants.INVOKESPECIAL;
import static org.eclipse.persistence.internal.libraries.asm.Constants.NEW;
import static org.eclipse.persistence.internal.libraries.asm.Constants.PUTSTATIC;
import static org.eclipse.persistence.internal.libraries.asm.Constants.RETURN;
import static org.eclipse.persistence.internal.libraries.asm.Constants.V1_5;
import static org.eclipse.persistence.internal.xr.XRDynamicClassLoader.COLLECTION_WRAPPER_SUFFIX;
import static org.eclipse.persistence.internal.xr.XRDynamicEntity.XR_FIELD_INFO_STATIC;
/**
* <p>
* <b>INTERNAL:</b> XRClassWriter uses ASM to dynamically
* generate subclasses of {@link XRDynamicEntity}
*
* @author Mike Norman - michael.norman@oracle.com
* @since EclipseLink 1.x
*/
public class XRClassWriter extends DynamicClassWriter {
private static final String XRFIELDINFO_CLASSNAME_SLASHES =
XRFieldInfo.class.getName().replace('.', '/');
private static final String XR_DYNAMIC_ENTITY_CLASSNAME_SLASHES =
XRDynamicEntity.class.getName().replace('.', '/');
private static final String XR_DYNAMIC_ENTITY_COLLECTION_CLASSNAME_SLASHES =
XRDynamicEntity_CollectionWrapper.class.getName().replace('.', '/');
public XRClassWriter() {
super();
}
@Override
public byte[] writeClass(DynamicClassLoader loader, String className) throws ClassNotFoundException {
/*
* Pattern is as follows:
*
* public class Foo extends XRDynamicEntity {
*
* public static XRFieldInfo XRFI = new XRFieldInfo();
*
* public Foo() {
* super();
* }
*
* @Override
* public XRFieldInfo getFieldInfo() {
* return XRFI;
* }
* }
*
* At some time later in the class' lifecycle, the XRFI
* static is populated with the required info w.r.t the index for a field
*/
String classNameAsSlashes = className.replace('.', '/');
ClassWriter cw = new ClassWriter(true);
CodeVisitor cv;
// special-case: build sub-class of XRDynamicEntityCollection
if (className.endsWith(COLLECTION_WRAPPER_SUFFIX)) {
cw.visit(V1_5, ACC_PUBLIC + ACC_SUPER, classNameAsSlashes,
XR_DYNAMIC_ENTITY_COLLECTION_CLASSNAME_SLASHES, null, null);
cv = cw.visitMethod(ACC_PUBLIC, INIT, "()V", null, null);
cv.visitVarInsn(ALOAD, 0);
cv.visitMethodInsn(INVOKESPECIAL, XR_DYNAMIC_ENTITY_COLLECTION_CLASSNAME_SLASHES,
INIT, "()V");
cv.visitInsn(RETURN);
cv.visitMaxs(0, 0);
}
else {
cw.visit(V1_5, ACC_PUBLIC + ACC_SUPER, classNameAsSlashes,
XR_DYNAMIC_ENTITY_CLASSNAME_SLASHES, null, null);
cw.visitField(ACC_PUBLIC + ACC_STATIC, XR_FIELD_INFO_STATIC,
"L" + XRFIELDINFO_CLASSNAME_SLASHES + ";", null, null);
cv = cw.visitMethod(ACC_STATIC, "<clinit>", "()V", null, null);
cv.visitTypeInsn(NEW, XRFIELDINFO_CLASSNAME_SLASHES);
cv.visitInsn(DUP);
cv.visitMethodInsn(INVOKESPECIAL, XRFIELDINFO_CLASSNAME_SLASHES, INIT, "()V");
cv.visitFieldInsn(PUTSTATIC, classNameAsSlashes, XR_FIELD_INFO_STATIC,
"L" + XRFIELDINFO_CLASSNAME_SLASHES + ";");
cv.visitInsn(RETURN);
cv.visitMaxs(0, 0);
cv = cw.visitMethod(ACC_PUBLIC, INIT, "()V", null, null);
cv.visitVarInsn(ALOAD, 0);
cv.visitMethodInsn(INVOKESPECIAL, XR_DYNAMIC_ENTITY_CLASSNAME_SLASHES, INIT, "()V");
cv.visitInsn(RETURN);
cv.visitMaxs(0, 0);
cv = cw.visitMethod(ACC_PUBLIC, "getFieldInfo",
"()L" + XRFIELDINFO_CLASSNAME_SLASHES + ";", null, null);
cv.visitFieldInsn(GETSTATIC, classNameAsSlashes, XR_FIELD_INFO_STATIC,
"L" + XRFIELDINFO_CLASSNAME_SLASHES + ";");
cv.visitInsn(ARETURN);
cv.visitMaxs(0, 0);
}
cw.visitEnd();
return cw.toByteArray();
}
}