org.hibernate.cache.ehcache.management.impl.BeanUtils Maven / Gradle / Ivy
/*
* Hibernate, Relational Persistence for Idiomatic Java
*
* License: GNU Lesser General Public License (LGPL), version 2.1 or later.
* See the lgpl.txt file in the root directory or .
*/
package org.hibernate.cache.ehcache.management.impl;
import java.lang.reflect.Field;
import java.lang.reflect.Method;
/**
* Reflective utilities for dealing with backward-incompatible change to statistics types in Hibernate 3.5.
*
* @author gkeim
*/
public class BeanUtils {
/**
* Return the named getter method on the bean or null if not found.
*
* @param bean The bean
* @param propertyName The property to get the getter for
*
* @return the named getter method
*/
private static Method getMethod(Object bean, String propertyName) {
final StringBuilder sb = new StringBuilder( "get" ).append( Character.toUpperCase( propertyName.charAt( 0 ) ) );
if ( propertyName.length() > 1 ) {
sb.append( propertyName.substring( 1 ) );
}
final String getterName = sb.toString();
for ( Method m : bean.getClass().getMethods() ) {
if ( getterName.equals( m.getName() ) && m.getParameterTypes().length == 0 ) {
return m;
}
}
return null;
}
private static Field getField(Object bean, String propertyName) {
for ( Field f : bean.getClass().getDeclaredFields() ) {
if ( propertyName.equals( f.getName() ) ) {
return f;
}
}
return null;
}
private static void validateArgs(Object bean, String propertyName) {
if ( bean == null ) {
throw new IllegalArgumentException( "bean is null" );
}
if ( propertyName == null ) {
throw new IllegalArgumentException( "propertyName is null" );
}
if ( propertyName.trim().length() == 0 ) {
throw new IllegalArgumentException( "propertyName is empty" );
}
}
/**
* Retrieve a named bean property value.
*
* @param bean The bean instance
* @param propertyName The name of the property whose value to extract
*
* @return the property value
*/
public static Object getBeanProperty(Object bean, String propertyName) {
validateArgs( bean, propertyName );
// try getters first
final Method getter = getMethod( bean, propertyName );
if ( getter != null ) {
try {
return getter.invoke( bean );
}
catch (Exception e) {
/**/
}
}
// then try fields
final Field field = getField( bean, propertyName );
if ( field != null ) {
try {
field.setAccessible( true );
return field.get( bean );
}
catch (Exception e) {
/**/
}
}
return null;
}
/**
* Retrieve a Long bean property value.
*
* @param bean The bean instance
* @param propertyName The name of the property whose value to extract
*
* @return long value
*
* @throws NoSuchFieldException If the value is null (wow)
*/
public static long getLongBeanProperty(final Object bean, final String propertyName) throws NoSuchFieldException {
validateArgs( bean, propertyName );
final Object o = getBeanProperty( bean, propertyName );
if ( o == null ) {
throw new NoSuchFieldException( propertyName );
}
else if ( !(o instanceof Number) ) {
throw new IllegalArgumentException( propertyName + " not an Number" );
}
return ((Number) o).longValue();
}
private BeanUtils() {
}
}