/*
* 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.cocoon.forms.binding;
import java.util.Collection;
import java.util.Iterator;
import java.util.Map;
import org.apache.avalon.framework.logger.AbstractLogEnabled;
import org.apache.cocoon.forms.binding.library.Library;
import org.apache.cocoon.forms.formmodel.Widget;
import org.apache.cocoon.util.jxpath.DOMFactory;
import org.apache.commons.jxpath.AbstractFactory;
import org.apache.commons.jxpath.JXPathContext;
import org.apache.commons.jxpath.Pointer;
import org.apache.commons.jxpath.ri.model.beans.BeanPropertyPointer;
import org.apache.commons.jxpath.util.TypeUtils;
import org.apache.commons.lang.exception.NestableRuntimeException;
/**
* Provides a base class for hooking up Binding implementations that use the
* Jakarta Commons <a href="http://jakarta.apache.org/commons/jxpath/index.html">
* JXPath package</a>.
*
* @version $Id$
*/
public abstract class JXPathBindingBase extends AbstractLogEnabled
implements Binding {
/**
* the local library, if this is the top binding
*/
private Library enclosingLibrary;
/**
* Object holding the values of the common objects on all Bindings.
*/
private final JXPathBindingBuilderBase.CommonAttributes commonAtts;
/**
* Parent binding of this binding.
*/
protected Binding parent;
/**
* Cache of class definitions
*/
protected Map classes;
protected JXPathBindingBase(JXPathBindingBuilderBase.CommonAttributes commonAtts) {
this.commonAtts = commonAtts;
}
/**
* @see org.apache.cocoon.forms.binding.Binding#getEnclosingLibrary()
*/
public Library getEnclosingLibrary() {
if (parent != null) {
return parent.getEnclosingLibrary();
} else {
return enclosingLibrary;
}
}
/**
* @see org.apache.cocoon.forms.binding.Binding#setEnclosingLibrary(org.apache.cocoon.forms.binding.library.Library)
*/
public void setEnclosingLibrary(Library lib) {
this.enclosingLibrary = lib;
}
/**
* @see org.apache.cocoon.forms.binding.Binding#isValid()
*/
public boolean isValid() {
if (this.enclosingLibrary == null) {
if (parent != null) {
return parent.isValid();
}
return true; // no library used
}
try {
return !this.enclosingLibrary.dependenciesHaveChanged();
} catch (Exception e) {
getLogger().error("Error checking dependencies!", e);
throw new NestableRuntimeException("Error checking dependencies!", e);
}
}
public JXPathBindingBuilderBase.CommonAttributes getCommonAtts() {
return this.commonAtts;
}
/**
* Gets source location of this binding.
*/
public String getLocation() {
return this.commonAtts.location;
}
/**
* Sets parent binding.
*/
public void setParent(Binding binding) {
this.parent = binding;
}
/**
* Returns binding definition id.
*/
public String getId() {
return null;
}
/**
* @see org.apache.cocoon.forms.binding.Binding#getClass(java.lang.String)
*/
public Binding getClass(String id) {
Binding classBinding = null;
try {
if (this.enclosingLibrary != null && (classBinding = this.enclosingLibrary.getBinding(id)) != null) {
return classBinding;
}
} catch (Exception e) { /* ignored */ }
if (classes != null) {
// Query cache for class
classBinding = (Binding)classes.get(id);
}
if (classBinding == null) {
// Query parent for class
if (parent != null) {
classBinding = parent.getClass(id);
// dont cache, doesn't matter and makes things complicated with libraries
// **************************************
// Cache result
/*if (classes == null) {
classes = new HashMap();
}
classes.put(id, classBinding);*/
// **************************************
} else {
throw new RuntimeException("Class \"" + id + "\" not found (" + getLocation() + ")");
}
}
return classBinding;
}
/**
* Helper method that selects a child-widget with a given id from a parent.
*
* @param parent containing the child-widget to return.
* @param id of the childWidget to find, if this is <code>null</code> then the parent is returned.
* @return the selected widget
*
* @throws RuntimeException if the id is not null and points to a
* child-widget that cannot be found.
*/
protected Widget selectWidget(Widget parent, String id) {
if (id == null) {
return parent;
}
Widget childWidget = parent.lookupWidget(id);
if (childWidget == null) {
String containerId = parent.getRequestParameterName();
if (containerId == null || "".equals(containerId)) {
containerId = "top-level form-widget";
} else {
containerId = "container \"" + containerId + "\"";
}
throw new RuntimeException(getClass().getName() + " (" + getLocation() + "): Widget \"" +
id + "\" does not exist in the " + containerId +
" (" + parent.getLocation() + ").");
}
return childWidget;
}
/**
* Performs the actual load binding regardless of the configured value of the "direction" attribute.
* Abstract method that subclasses need to implement for specific activity.
*/
public abstract void doLoad(Widget frmModel, JXPathContext jxpc)
throws BindingException;
/**
* Redefines the Binding action as working on a JXPathContext Type rather
* then on generic objects.
* Executes the actual loading via {@link #doLoad(Widget, JXPathContext)}
* depending on the configured value of the "direction" attribute.
*/
public final void loadFormFromModel(Widget frmModel, JXPathContext jxpc)
throws BindingException {
boolean inheritedLeniency = jxpc.isLenient();
applyLeniency(jxpc);
applyNSDeclarations(jxpc);
if (this.commonAtts.loadEnabled) {
doLoad(frmModel, jxpc);
}
jxpc.setLenient(inheritedLeniency);
}
/**
* Hooks up with the more generic Binding of any objectModel by wrapping
* it up in a JXPathContext object and then transfering control over to
* the new overloaded version of this method.
*
* @see org.apache.cocoon.forms.binding.Binding#loadFormFromModel(org.apache.cocoon.forms.formmodel.Widget, java.lang.Object)
*/
public final void loadFormFromModel(Widget frmModel, Object objModel)
throws BindingException {
if (objModel != null) {
JXPathContext jxpc = makeJXPathContext(objModel);
loadFormFromModel(frmModel, jxpc);
} else {
throw new NullPointerException(
"null object passed to loadFormFromModel() method");
}
}
/**
* Performs the actual save binding regardless of the configured value of the "direction" attribute.
* Abstract method that subclasses need to implement for specific activity.
*/
public abstract void doSave(Widget frmModel, JXPathContext jxpc)
throws BindingException;
/**
* Redefines the Binding action as working on a JXPathContext Type rather
* then on generic objects.
* Executes the actual saving via {@link #doSave(Widget, JXPathContext)}
* depending on the configured value of the "direction" attribute.
*/
public final void saveFormToModel(Widget frmModel, JXPathContext jxpc)
throws BindingException{
boolean inheritedLeniency = jxpc.isLenient();
applyLeniency(jxpc);
applyNSDeclarations(jxpc);
if (this.commonAtts.saveEnabled) {
doSave(frmModel, jxpc);
}
jxpc.setLenient(inheritedLeniency);
}
/**
* Hooks up with the more generic Binding of any objectModel by wrapping
* it up in a JXPathContext object and then transfering control over to
* the new overloaded version of this method.
*
* @see org.apache.cocoon.forms.binding.Binding#saveFormToModel(org.apache.cocoon.forms.formmodel.Widget, java.lang.Object)
*/
public void saveFormToModel(Widget frmModel, Object objModel)
throws BindingException {
if (objModel != null) {
JXPathContext jxpc = makeJXPathContext(objModel);
saveFormToModel(frmModel, jxpc);
} else {
throw new NullPointerException(
"null object passed to saveFormToModel() method");
}
}
private void applyLeniency(JXPathContext jxpc) {
if (this.commonAtts.leniency != null) {
jxpc.setLenient(this.commonAtts.leniency.booleanValue());
}
}
private void applyNSDeclarations(JXPathContext jxpc) {
if (this.commonAtts.nsDeclarations != null) {
Iterator keysIter = this.commonAtts.nsDeclarations.keySet().iterator();
while (keysIter.hasNext()) {
String nsuri = (String) keysIter.next();
String pfx = (String) this.commonAtts.nsDeclarations.get(nsuri);
jxpc.registerNamespace(pfx, nsuri);
}
}
}
private JXPathContext makeJXPathContext(Object objModel) {
JXPathContext jxpc;
if (!(objModel instanceof JXPathContext)) {
jxpc = JXPathContext.newContext(objModel);
jxpc.setLenient(true);
AbstractFactory jxPathFactory;
if (commonAtts.jxPathFactory != null)
jxPathFactory = commonAtts.jxPathFactory;
else
jxPathFactory = new BindingJXPathFactory();
jxpc.setFactory(jxPathFactory);
} else {
jxpc = (JXPathContext) objModel;
}
return jxpc;
}
/**
* JXPath factory that combines the DOMFactory and support for collections.
*/
private static class BindingJXPathFactory extends DOMFactory {
public boolean createObject(JXPathContext context, Pointer pointer, Object parent, String name, int index) {
if (createCollectionItem(context, pointer, parent, name, index)) {
return true;
// AG: If this is a bean, then the object is supposed to exists.
} else if (pointer instanceof BeanPropertyPointer) {
return createBeanField(context, pointer, parent, name, index);
} else {
return super.createObject(context, pointer, parent, name, index);
}
}
private boolean createCollectionItem(JXPathContext context, Pointer pointer, Object parent, String name, int index) {
// FIXME: don't clearly understand how this works.
// see http://marc.theaimsgroup.com/?l=xml-cocoon-dev&m=111148567029114&w=2
final Object o = context.getValue(name);
if (o == null) {
return false;
}
if (o instanceof Collection) {
((Collection)o).add(null);
} else if(o.getClass().isArray()) {
// not yet supported
return false;
} else {
return false;
}
return true;
}
// AG: Create the Object for the field as defined in the Bean.
// The value we will set here is not important. JXPath knows that it is UNITIALIZED.
// if we set it Pointer Value to null then the code will throw an exception.
//
// In short, there is no harm. The value will never show up.
// TODO: Manage other forms' types as Date, Bean and others not covered by this method.
private boolean createBeanField(JXPathContext context, Pointer pointer, Object parent, String name, int index) {
try {
Class clazz = parent.getClass().getDeclaredField(name).getType();
Object o = context.getValue(name);
if (o == null) {
final Class[] parametersTypes = {String.class};
final Object[] initArgs = {"0"};
try {
// AG: Here we service Booleans, Strings and Number() + his Direct know subclasses:
// (BigDecimal, BigInteger, Byte, Double, Float, Integer, Long, Short)
// as well as other classes that use an String as Constructor parameter.
o = clazz.getConstructor(parametersTypes).newInstance(initArgs);
} catch (Exception e) {
// AG: The class has not a constructor using a String as a parameter.
// ie: Boolean(String), Integer(String), etc.
// Lets try with a constructor with no parameters. ie: Number().
o = clazz.newInstance();
}
} else if (TypeUtils.canConvert(o, clazz)) {
o = TypeUtils.convert(o, clazz);
}
if (o != null) {
pointer.setValue(o);
return true; // OK. We have an initial Object of the right Class initialized.
}
} catch (Exception e) {
// TODO: Output info in logs.
}
return false;
}
}
}