/*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you 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.apache.openjpa.lib.meta;
import java.security.AccessController;
import org.apache.openjpa.lib.util.StringUtil;
import org.apache.openjpa.lib.util.ClassUtil;
import org.apache.openjpa.lib.util.J2DoPrivHelper;
import org.apache.openjpa.lib.util.Localizer;
import org.xml.sax.Attributes;
import org.xml.sax.SAXException;
/**
* Custom SAX parser used by the system to quickly parse metadata files
* for classes.
*
* @author Abe White
*/
public class CFMetaDataParser extends XMLMetaDataParser {
static final String[] PACKAGES = new String[]{
"java.lang.", "java.util.", "java.math." };
private static final Localizer _loc = Localizer.forPackage
(CFMetaDataParser.class);
// the current package and class being parsed
private String _package = null;
private String _class = null;
public CFMetaDataParser() {
setParseText(false);
}
/**
* The name of the package element. Defaults to "package".
*/
protected boolean isPackageElementName(String name) {
return "package".equals(name);
}
/**
* The attribute of the package element that holds the name, or null to
* use the element text. Defaults to "name".
*/
protected String getPackageAttributeName() {
return "name";
}
/**
* The depth of the package element. Defaults to 1.
*/
protected int getPackageElementDepth() {
return 1;
}
/**
* The name of the class element. Defaults to "class".
*/
protected boolean isClassElementName(String name) {
return "class".equals(name);
}
/**
* The attribute of the class element that holds the name, or null to
* use the element text. Defaults to "name".
*/
protected String getClassAttributeName() {
return "name";
}
/**
* The depth of the class element. Defaults to 2.
*/
protected int getClassElementDepth() {
return 2;
}
protected boolean startElement(String name, Attributes attrs)
throws SAXException {
// skip root element
int depth = currentDepth();
if (depth == 0)
return true;
if (StringUtil.contains(name, ':')) {
int index = name.indexOf(':');
name = name.substring(index + 1);
}
try {
if (_openjpaNamespace > 0) {
if (name.equals("entity"))
return startExtendedClass(name,attrs);
if (name.equals("attributes")) {
return true;
}
return startClassElement(name, attrs);
}
if (depth == getPackageElementDepth()
&& isPackageElementName(name))
return startPackage(name, attrs);
if (depth == getClassElementDepth() && isClassElementName(name))
return startClass(name, attrs);
if (depth > getClassElementDepth() && _class != null
&& getClassAttributeName() != null)
return startClassElement(name, attrs);
if (depth > getPackageElementDepth() && _package != null
&& getPackageAttributeName() != null)
return startPackageElement(name, attrs);
return startSystemElement(name, attrs);
} catch (SAXException se) {
throw se;
} catch (NullPointerException npe) {
throw getException(_loc.get("parse-error", name), npe);
}
}
protected void endElement(String name) throws SAXException {
// skip root element
int depth = currentDepth();
if (depth == 0)
return;
if (StringUtil.contains(name, ':')) {
int index = name.indexOf(':');
name = name.substring(index + 1);
}
try {
if (_openjpaNamespace > 0) {
if (name.equals("entity"))
endExtendedClass(name);
else if (name.equals("attributes")) {
// do nothing
}
else {
endClassElement(name);
}
}
else if (depth == getPackageElementDepth()
&& isPackageElementName(name))
endPackage(name);
else if (depth == getClassElementDepth()
&& isClassElementName(name))
endClass(name);
else if (depth > getClassElementDepth() && _class != null
&& getClassAttributeName() != null)
endClassElement(name);
else if (depth > getPackageElementDepth() && _package != null
&& getPackageAttributeName() != null)
endPackageElement(name);
else
endSystemElement(name);
} catch (SAXException se) {
throw se;
} catch (NullPointerException npe) {
throw getException(_loc.get("parse-error", name), npe);
}
}
/**
* Start a package. Parses out package attribute by default.
* Return false to skip package element and its contents.
*/
protected boolean startPackage(String elem, Attributes attrs)
throws SAXException {
if (getPackageAttributeName() != null) {
_package = attrs.getValue(getPackageAttributeName());
if (_package == null)
_package = "";
}
return true;
}
/**
* End a package. Parses contained text by default.
*/
protected void endPackage(String elem) {
if (getPackageAttributeName() != null)
_package = null;
else
_package = currentText();
}
/**
* Start a class. Parses out class name by default. Return
* false to skip class element and its contents.
*/
protected boolean startClass(String elem, Attributes attrs)
throws SAXException {
if (getClassAttributeName() != null) {
_class = attrs.getValue(getClassAttributeName());
if (!StringUtil.isEmpty(_package) && _class.indexOf('.') == -1)
_class = _package + "." + _class;
}
return true;
}
/**
* End a class. Parses contained text by default.
*/
protected void endClass(String elem) throws SAXException {
if (getClassAttributeName() != null)
_class = null;
else {
_class = currentText();
if (!StringUtil.isEmpty(_package) && _class.indexOf('.') == -1)
_class = _package + "." + _class;
}
}
protected boolean startExtendedClass(String elem, Attributes attrs)
throws SAXException {
return false;
}
protected void endExtendedClass(String elem) throws SAXException {
}
/**
* Override this method marking the start of an element outside of any
* package or class.
*/
protected boolean startSystemElement(String name, Attributes attrs)
throws SAXException {
return false;
}
/**
* Override this method marking the end of an element outside of any
* package or class.
*/
protected void endSystemElement(String name) throws SAXException {
}
/**
* Override this method marking the start of an element within a declared
* package.
*/
protected boolean startPackageElement(String name, Attributes attrs)
throws SAXException {
return false;
}
/**
* Override this method marking the end of an element within a declared
* package.
*/
protected void endPackageElement(String name) throws SAXException {
}
/**
* Override this method marking the start of an element within a declared
* class.
*/
protected boolean startClassElement(String name, Attributes attrs)
throws SAXException {
return false;
}
/**
* Override this method marking the end of an element within a declared
* class.
*/
protected void endClassElement(String name) throws SAXException {
}
/**
* Override this method to clear any state and ready the parser for
* a new document. Subclasses should call
* <code>super.reset()</code> to clear superclass state.
*/
protected void reset() {
super.reset();
_package = null;
_class = null;
}
/**
* Return the current class being parsed; the returned name will
* be fully qualified.
*/
protected String currentClassName() {
return _class;
}
/**
* Return the current package being parsed.
*/
protected String currentPackage() {
return _package;
}
/**
* Helper method to create the {@link Class} for the given name,
* taking into account the package currently being parsed for relative
* class names.
*/
protected Class<?> classForName(String name, boolean resolve)
throws SAXException {
if (name == null)
return null;
Class<?> cls =
classForName(name, _package, resolve, currentClassLoader());
if (cls == null)
throw getException(_loc.get("invalid-class", name).getMessage());
return cls;
}
/**
* Load the given class name against the given package and the set
* of accepted standard packages. Return null if the class cannot be loaded.
*/
public static Class<?> classForName(String name, String pkg,
boolean resolve, ClassLoader loader) {
if (StringUtil.isEmpty(name))
return null;
if (loader == null)
loader = AccessController.doPrivileged(
J2DoPrivHelper.getContextClassLoaderAction());
boolean fullName = name.indexOf('.') != -1;
boolean noPackage = StringUtil.isEmpty(pkg);
try {
if (fullName || noPackage)
return ClassUtil.toClass(name, resolve, loader);
return ClassUtil.toClass(pkg + "." + name, resolve, loader);
} catch (RuntimeException re) {
}
// if not a full name, now try the name without a package
if (!fullName && !noPackage) {
try {
return ClassUtil.toClass(name, resolve, loader);
} catch (RuntimeException re) {
}
}
// try with standard packages
if (!fullName) {
for (int i = 0; i < PACKAGES.length; i++) {
try {
return ClassUtil.toClass(PACKAGES[i] + name, resolve, loader);
} catch (RuntimeException re) {
}
}
}
return null;
}
}