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Javascript/CSS bundling and compressing tool for java web apps.
By using jawr resources are automatically bundled together and optionally minified and gzipped.
Jawr provides tag libraries to reference a generated bundle either by id or by using the name of any of its members.
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/**
* Copyright 2009-2016 Ibrahim Chaehoi
*
* 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.
*/
package net.jawr.web.util;
import java.beans.BeanInfo;
import java.beans.IntrospectionException;
import java.beans.Introspector;
import java.beans.PropertyDescriptor;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
/**
* Utility methods for using Java Reflection APIs to facilitate generic property
* getter and setter operations on Java objects. This is a slightly modified
* version of PropertyUtilsBean.
*
* @author Ibrahim Chaehoi
*
*/
public class PropertyUtils {
/** The logger */
private static final Logger LOGGER = LoggerFactory.getLogger(PropertyUtils.class);
/**
* Return the value of the specified simple property of the specified bean,
* with string conversions.
*
* @param bean
* Bean whose property is to be extracted
* @param name
* Name of the property to be extracted
* @return the value of the specified simple property of the specified bean,
* with string conversions.
*
* @exception IllegalAccessException
* if the caller does not have access to the property
* accessor method
* @exception IllegalArgumentException
* if bean or name is null
* @exception IllegalArgumentException
* if the property name is nested or indexed
* @exception InvocationTargetException
* if the property accessor method throws an exception
* @exception NoSuchMethodException
* if an accessor method for this propety cannot be found
*/
public static String getProperty(Object bean, String name)
throws NoSuchMethodException, IllegalAccessException, InvocationTargetException {
String value = null;
// Retrieve the property getter method for the specified property
PropertyDescriptor descriptor = getPropertyDescriptor(bean, name);
if (descriptor == null) {
throw new NoSuchMethodException("Unknown property '" + name + "'");
}
Method readMethod = descriptor.getReadMethod();
if (readMethod == null) {
throw new NoSuchMethodException("Property '" + name + "' has no getter method");
}
// Call the property getter and return the value
Object result = (Object) invokeMethod(readMethod, bean, new Object[0]);
if (result != null) {
value = result.toString();
}
return value;
}
/**
*
* Retrieve the property descriptor for the specified property of the
* specified bean, or return null if there is no such
* descriptor. This method resolves indexed and nested property references
* in the same manner as other methods in this class, except that if the
* last (or only) name element is indexed, the descriptor for the last
* resolved property itself is returned.
*
*
* @param bean
* Bean for which a property descriptor is requested
* @param name
* Possibly indexed and/or nested name of the property for which
* a property descriptor is requested
*
* @exception IllegalAccessException
* if the caller does not have access to the property
* accessor method
* @exception IllegalArgumentException
* if bean or name is null
* @exception IllegalArgumentException
* if a nested reference to a property returns null
* @exception InvocationTargetException
* if the property accessor method throws an exception
* @exception NoSuchMethodException
* if an accessor method for this propety cannot be found
*/
private static PropertyDescriptor getPropertyDescriptor(Object bean, String name) {
PropertyDescriptor descriptor = null;
PropertyDescriptor descriptors[] = getPropertyDescriptors(bean.getClass());
if (descriptors != null) {
for (PropertyDescriptor descriptor1 : descriptors) {
if (name.equals(descriptor1.getName())) {
descriptor = descriptor1;
}
}
}
return descriptor;
}
/**
*
* Retrieve the property descriptors for the specified class, introspecting
* and caching them the first time a particular bean class is encountered.
*
*
* @param beanClass
* Bean class for which property descriptors are requested
* @return the property descriptors
*
* @exception IllegalArgumentException
* if beanClass is null
*/
public static PropertyDescriptor[] getPropertyDescriptors(Class beanClass) {
if (beanClass == null) {
throw new IllegalArgumentException("No bean class specified");
}
// Look up any cached descriptors for this bean class
PropertyDescriptor descriptors[] = null;
// Introspect the bean and cache the generated descriptors
BeanInfo beanInfo = null;
try {
beanInfo = Introspector.getBeanInfo(beanClass);
} catch (IntrospectionException e) {
return (new PropertyDescriptor[0]);
}
descriptors = beanInfo.getPropertyDescriptors();
if (descriptors == null) {
descriptors = new PropertyDescriptor[0];
}
return (descriptors);
}
/**
* Set the value of the specified simple property of the specified bean,
* with no type conversions.
*
* @param bean
* Bean whose property is to be modified
* @param name
* Name of the property to be modified
* @param value
* Value to which the property should be set
*
* @exception IllegalAccessException
* if the caller does not have access to the property
* accessor method
* @exception IllegalArgumentException
* if bean or name is null
* @exception IllegalArgumentException
* if the property name is nested or indexed
* @exception InvocationTargetException
* if the property accessor method throws an exception
* @exception NoSuchMethodException
* if an accessor method for this propety cannot be found
*/
public static void setProperty(Object bean, String name, Object value)
throws IllegalAccessException, InvocationTargetException, NoSuchMethodException {
if (bean == null) {
throw new IllegalArgumentException("No bean specified");
}
if (name == null) {
throw new IllegalArgumentException("No name specified");
}
// Retrieve the property setter method for the specified property
PropertyDescriptor descriptor = getPropertyDescriptor(bean, name);
if (descriptor == null) {
throw new NoSuchMethodException("Unknown property '" + name + "'");
}
Method writeMethod = descriptor.getWriteMethod();
if (writeMethod == null) {
throw new NoSuchMethodException("Property '" + name + "' has no setter method");
}
// Call the property setter method
Object values[] = new Object[1];
values[0] = value;
invokeMethod(writeMethod, bean, values);
}
/**
* This utility method just catches and wraps IllegalArgumentException.
*
* @param method
* the method to call
* @param bean
* the bean
* @param values
* the values
* @return the returned value of the method
* @throws IllegalAccessException
* if an exception occurs
* @throws InvocationTargetException
* if an exception occurs
*/
private static Object invokeMethod(Method method, Object bean, Object[] values)
throws IllegalAccessException, InvocationTargetException {
try {
return method.invoke(bean, values);
} catch (IllegalArgumentException e) {
LOGGER.error("Method invocation failed.", e);
throw new IllegalArgumentException("Cannot invoke " + method.getDeclaringClass().getName() + "."
+ method.getName() + " - " + e.getMessage());
}
}
}