/* $Id: SetRootRule.java 992060 2010-09-02 19:09:47Z simonetripodi $
*
* 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.commons.digester;
import org.apache.commons.beanutils.MethodUtils;
Rule implementation that calls a method on the root object on the stack,
passing the top object (child) as an argument.
It is important to remember that this rule acts on end.
This rule now supports more flexible method matching by default. It is possible that this may break (some) code written against release 1.1.1 or earlier. See isExactMatch() for more details.
/**
* <p>Rule implementation that calls a method on the root object on the stack,
* passing the top object (child) as an argument.
* It is important to remember that this rule acts on <code>end</code>.</p>
*
* <p>This rule now supports more flexible method matching by default.
* It is possible that this may break (some) code
* written against release 1.1.1 or earlier.
* See {@link #isExactMatch()} for more details.</p>
*/
public class SetRootRule extends Rule {
// ----------------------------------------------------------- Constructors
Construct a "set root" rule with the specified method name. The
method's argument type is assumed to be the class of the
child object.
Params: - digester – The associated Digester
- methodName – Method name of the parent method to call
Deprecated: The digester instance is now set in the Digester.addRule method. Use SetRootRule(String methodName) instead.
/**
* Construct a "set root" rule with the specified method name. The
* method's argument type is assumed to be the class of the
* child object.
*
* @param digester The associated Digester
* @param methodName Method name of the parent method to call
*
* @deprecated The digester instance is now set in the {@link Digester#addRule} method.
* Use {@link #SetRootRule(String methodName)} instead.
*/
@Deprecated
public SetRootRule(Digester digester, String methodName) {
this(methodName);
}
Construct a "set root" rule with the specified method name.
Params: - digester – The associated Digester
- methodName – Method name of the parent method to call
- paramType – Java class of the parent method's argument
(if you wish to use a primitive type, specify the corresonding
Java wrapper class instead, such as
java.lang.Boolean
for a boolean parameter)
Deprecated: The digester instance is now set in the Digester.addRule method. Use SetRootRule(String methodName, String paramType) instead.
/**
* Construct a "set root" rule with the specified method name.
*
* @param digester The associated Digester
* @param methodName Method name of the parent method to call
* @param paramType Java class of the parent method's argument
* (if you wish to use a primitive type, specify the corresonding
* Java wrapper class instead, such as <code>java.lang.Boolean</code>
* for a <code>boolean</code> parameter)
*
* @deprecated The digester instance is now set in the {@link Digester#addRule} method.
* Use {@link #SetRootRule(String methodName,String paramType)} instead.
*/
@Deprecated
public SetRootRule(Digester digester, String methodName,
String paramType) {
this(methodName, paramType);
}
Construct a "set root" rule with the specified method name. The
method's argument type is assumed to be the class of the
child object.
Params: - methodName – Method name of the parent method to call
/**
* Construct a "set root" rule with the specified method name. The
* method's argument type is assumed to be the class of the
* child object.
*
* @param methodName Method name of the parent method to call
*/
public SetRootRule(String methodName) {
this(methodName, null);
}
Construct a "set root" rule with the specified method name.
Params: - methodName – Method name of the parent method to call
- paramType – Java class of the parent method's argument
(if you wish to use a primitive type, specify the corresonding
Java wrapper class instead, such as
java.lang.Boolean
for a boolean parameter)
/**
* Construct a "set root" rule with the specified method name.
*
* @param methodName Method name of the parent method to call
* @param paramType Java class of the parent method's argument
* (if you wish to use a primitive type, specify the corresonding
* Java wrapper class instead, such as <code>java.lang.Boolean</code>
* for a <code>boolean</code> parameter)
*/
public SetRootRule(String methodName,
String paramType) {
this.methodName = methodName;
this.paramType = paramType;
}
// ----------------------------------------------------- Instance Variables
The method name to call on the parent object.
/**
* The method name to call on the parent object.
*/
protected String methodName = null;
The Java class name of the parameter type expected by the method.
/**
* The Java class name of the parameter type expected by the method.
*/
protected String paramType = null;
Should we use exact matching. Default is no.
/**
* Should we use exact matching. Default is no.
*/
protected boolean useExactMatch = false;
// --------------------------------------------------------- Public Methods
Is exact matching being used.
This rule uses org.apache.commons.beanutils.MethodUtils
to introspect the relevent objects so that the right method can be called.
Originally, MethodUtils.invokeExactMethod was used.
This matches methods very strictly
and so may not find a matching method when one exists.
This is still the behaviour when exact matching is enabled.
When exact matching is disabled, MethodUtils.invokeMethod is used.
This method finds more methods but is less precise when there are several methods
with correct signatures.
So, if you want to choose an exact signature you might need to enable this property.
The default setting is to disable exact matches.
Returns: true iff exact matching is enabled Since: Digester Release 1.1.1
/**
* <p>Is exact matching being used.</p>
*
* <p>This rule uses <code>org.apache.commons.beanutils.MethodUtils</code>
* to introspect the relevent objects so that the right method can be called.
* Originally, <code>MethodUtils.invokeExactMethod</code> was used.
* This matches methods very strictly
* and so may not find a matching method when one exists.
* This is still the behaviour when exact matching is enabled.</p>
*
* <p>When exact matching is disabled, <code>MethodUtils.invokeMethod</code> is used.
* This method finds more methods but is less precise when there are several methods
* with correct signatures.
* So, if you want to choose an exact signature you might need to enable this property.</p>
*
* <p>The default setting is to disable exact matches.</p>
*
* @return true iff exact matching is enabled
* @since Digester Release 1.1.1
*/
public boolean isExactMatch() {
return useExactMatch;
}
Set whether exact matching is enabled.
See isExactMatch().
Params: - useExactMatch – should this rule use exact method matching
Since: Digester Release 1.1.1
/**
* <p>Set whether exact matching is enabled.</p>
*
* <p>See {@link #isExactMatch()}.</p>
*
* @param useExactMatch should this rule use exact method matching
* @since Digester Release 1.1.1
*/
public void setExactMatch(boolean useExactMatch) {
this.useExactMatch = useExactMatch;
}
Process the end of this element.
/**
* Process the end of this element.
*/
@Override
public void end() throws Exception {
// Identify the objects to be used
Object child = digester.peek(0);
Object parent = digester.root;
if (digester.log.isDebugEnabled()) {
if (parent == null) {
digester.log.debug("[SetRootRule]{" + digester.match +
"} Call [NULL ROOT]." +
methodName + "(" + child + ")");
} else {
digester.log.debug("[SetRootRule]{" + digester.match +
"} Call " + parent.getClass().getName() + "." +
methodName + "(" + child + ")");
}
}
// Call the specified method
Class<?> paramTypes[] = new Class<?>[1];
if (paramType != null) {
paramTypes[0] =
digester.getClassLoader().loadClass(paramType);
} else {
paramTypes[0] = child.getClass();
}
if (useExactMatch) {
MethodUtils.invokeExactMethod(parent, methodName,
new Object[]{ child }, paramTypes);
} else {
MethodUtils.invokeMethod(parent, methodName,
new Object[]{ child }, paramTypes);
}
}
Render a printable version of this Rule.
/**
* Render a printable version of this Rule.
*/
@Override
public String toString() {
StringBuffer sb = new StringBuffer("SetRootRule[");
sb.append("methodName=");
sb.append(methodName);
sb.append(", paramType=");
sb.append(paramType);
sb.append("]");
return (sb.toString());
}
}