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/**
* Copyright 2015 Santhosh Kumar Tekuri
*
* The JLibs authors license 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 jlibs.core.lang;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import java.util.Locale;
/**
* This class contains helper methods for working with java beans
*
* @author Santhosh Kumar T
*/
public class BeanUtil{
public static String getMethodSuffix(String property){
switch(property.length()){
case 0:
throw new IllegalArgumentException("invalid property name: "+property);
case 1:
return property.toUpperCase(Locale.ENGLISH);
default:
char char0 = property.charAt(0);
boolean upper0 = Character.isUpperCase(char0);
char char1 = property.charAt(1);
boolean upper1 = Character.isUpperCase(char1);
if(upper0 && upper1) // XCoordinate ==> getXCordinate()
return property;
if(!upper0 && !upper1) // xcoordinate ==> getXcoordinate()
return Character.toUpperCase(char0)+property.substring(1);
if(!upper0 && upper1) // xCoordinate ==> getxCoordinate()
return property;
throw new IllegalArgumentException("invalid property name: "+property);
}
}
@SuppressWarnings({"ConstantConditions"})
public static String getPropertyName(String methodName){
String suffix;
if(methodName.startsWith(GET) || methodName.startsWith(SET))
suffix = methodName.substring(3);
else if(methodName.startsWith(IS))
suffix = methodName.substring(2);
else
throw new IllegalArgumentException("invalid method name: "+methodName);
switch(suffix.length()){
case 0:
throw new IllegalArgumentException("invalid method name: "+methodName);
case 1:
return suffix.toLowerCase(Locale.ENGLISH);
default:
char char0 = suffix.charAt(0);
boolean upper0 = Character.isUpperCase(char0);
char char1 = suffix.charAt(1);
boolean upper1 = Character.isUpperCase(char1);
if(upper0 && upper1) // getXCordinate() ==> XCoordinate
return suffix;
if(upper0 && !upper1) // getXcoordinate() ==> xcoordinate
return Character.toLowerCase(char0)+suffix.substring(1);
if(!upper0 && upper1) // getxCoordinate() ==> xCoordinate
return suffix;
throw new IllegalArgumentException("invalid method name: "+methodName);
}
}
/*-------------------------------------------------[ Getter Method ]---------------------------------------------------*/
/** prefix used by non-boolean getter methods */
public static final String GET = "get"; //NOI18N
/** prefix used by boolean getter methods */
public static final String IS = "is"; //NOI18N
/**
* Returns getter method for property in specified beanClass
*
* @param beanClass bean class
* @param property name of the property
*
* @return getter method. null if property is not found
*
* @see #getGetterMethod(Class, String, Class)
*/
public static Method getGetterMethod(Class beanClass, String property){
try{
return beanClass.getMethod(GET+getMethodSuffix(property));
}catch(NoSuchMethodException ex1){
try{
return beanClass.getMethod(IS+getMethodSuffix(property));
}catch(NoSuchMethodException ex2){
return null;
}
}
}
/**
* Returns getter method for property in specified beanClass
*
* @param beanClass bean class
* @param property name of the property
* @param propertyType type of the property. This is used to compute getter method name.
*
* @return getter method. null if property is not found
*
* @see #getGetterMethod(Class, String)
*/
public static Method getGetterMethod(Class beanClass, String property, Class propertyType){
try{
try{
if(propertyType==boolean.class)
return beanClass.getMethod(IS+getMethodSuffix(property));
}catch(NoSuchMethodException ignore){
// ignore
}
return beanClass.getMethod(GET+getMethodSuffix(property));
}catch(NoSuchMethodException ex){
return null;
}
}
/*-------------------------------------------------[ Setter Method ]---------------------------------------------------*/
/**
* Returns setter method for property in specified beanClass
*
* @param beanClass bean class
* @param property name of the property
*
* @return setter method. null if property is not found, or it is readonly property
*
* @see #getSetterMethod(Class, String, Class)
*/
public static Method getSetterMethod(Class beanClass, String property){
Method getter = getGetterMethod(beanClass, property);
if(getter==null)
return null;
else
return getSetterMethod(beanClass, property, getter.getReturnType());
}
/** prefix used by setter methods */
public static final String SET = "set"; //NOI18N
/**
* Returns setter method for property in specified beanClass
*
* @param beanClass bean class
* @param property name of the property
* @param propertyType type of the property. This is used to compute setter method name.
*
* @return setter method. null if property is not found, or it is readonly property
*
* @see #getSetterMethod(Class, String)
*/
public static Method getSetterMethod(Class beanClass, String property, Class propertyType){
try{
return beanClass.getMethod(SET+getMethodSuffix(property), propertyType);
} catch(NoSuchMethodException ex){
return null;
}
}
/*-------------------------------------------------[ Property ]---------------------------------------------------*/
/**
* Returns the type of property in given beanClass
*
* @param beanClass bean class
* @param property name of the property
*
* @return null if the property is not found. otherwise returns the type of the property
*/
public static Class getPropertyType(Class beanClass, String property){
Method getter = getGetterMethod(beanClass, property);
if(getter==null)
return null;
else
return getter.getReturnType();
}
/**
* Returns the value of the specified property in given bean
*
* @param bean bean object
* @param property property name whose value needs to be returned
*
* @return value of the property.
*
* @throws InvocationTargetException if method invocation fails
* @throws NullPointerException if property is not found in bean
*/
@SuppressWarnings({"unchecked"})
public static T getProperty(Object bean, String property) throws InvocationTargetException{
try{
return (T)getGetterMethod(bean.getClass(), property).invoke(bean);
}catch(IllegalAccessException ex){
throw new ImpossibleException(ex); // because getter method is public
}
}
/**
* Sets the value of the specified property in given bean
*
* @param bean bean object
* @param property property name whose value needs to be set
* @param value value to be set
*
* @throws InvocationTargetException if method invocation fails
* @throws NullPointerException if property is not found in bean or it is readonly property
*/
public static void setProperty(Object bean, String property, Object value) throws InvocationTargetException{
try{
getSetterMethod(bean.getClass(), property).invoke(bean, value);
}catch(IllegalAccessException ex){
throw new ImpossibleException(ex); // because setter method is public
}
}
}