/*
* Copyright (C) 2006-2013 Bitronix Software (http://www.bitronix.be)
*
* 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 bitronix.tm.utils;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import java.lang.reflect.Modifier;
import java.util.HashMap;
import java.util.Iterator;
import java.util.Map;
import java.util.TreeMap;
/**
* Smart reflection helper.
*
* @author Ludovic Orban
*/
public final class PropertyUtils {
private PropertyUtils() {
}
/**
* Set a direct or indirect property (dotted property: prop1.prop2.prop3) on the target object. This method tries
* to be smart in the way that intermediate properties currently set to null are set if it is possible to create
* and set an object. Conversions from propertyValue to the proper destination type are performed when possible.
* @param target the target object on which to set the property.
* @param propertyName the name of the property to set.
* @param propertyValue the value of the property to set.
* @throws PropertyException if an error happened while trying to set the property.
*/
public static void setProperty(Object target, String propertyName, Object propertyValue) throws PropertyException {
String[] propertyNames = propertyName.split("\\.");
StringBuilder visitedPropertyName = new StringBuilder();
Object currentTarget = target;
Object parentTarget = target;
String parentName = null;
int i = 0;
while (i < propertyNames.length -1) {
String name = propertyNames[i];
Object result = callGetter(currentTarget, name);
if (result == null) {
// try to instantiate the object & set it in place
Class<?> propertyType = getPropertyType(target, name);
try {
result = propertyType.newInstance();
} catch (InstantiationException ex) {
throw new PropertyException("cannot set property '" + propertyName + "' - '" + name + "' is null and cannot be auto-filled", ex);
} catch (IllegalAccessException ex) {
throw new PropertyException("cannot set property '" + propertyName + "' - '" + name + "' is null and cannot be auto-filled", ex);
}
callSetter(currentTarget, name, result);
}
parentTarget = currentTarget;
currentTarget = result;
visitedPropertyName.append(name);
visitedPropertyName.append('.');
i++;
// if it's a Map object -> the non-visited part of the key should be used
// as this Map's object key so stop iterating over the dotted properties.
if (currentTarget instanceof Map) {
parentName = name;
break;
}
}
String lastPropertyName = propertyName.substring(visitedPropertyName.length(), propertyName.length());
if (currentTarget instanceof Map) {
@SuppressWarnings("unchecked")
Map<String, Object> p = (Map<String, Object>) currentTarget;
p.put(lastPropertyName, propertyValue.toString());
if (parentName != null) {
callSetter(parentTarget, parentName, p);
}
} else {
setDirectProperty(currentTarget, lastPropertyName, propertyValue);
}
}
/**
* Build a map of direct javabeans properties of the target object. Only read/write properties (ie: those who have
* both a getter and a setter) are returned.
* @param target the target object from which to get properties names.
* @return a Map of String with properties names as key and their values
* @throws PropertyException if an error happened while trying to get a property.
*/
public static Map<String, Object> getProperties(Object target) throws PropertyException {
Map<String, Object> properties = new HashMap<String, Object>();
Class<?> clazz = target.getClass();
Method[] methods = clazz.getMethods();
for (Method method : methods) {
String name = method.getName();
if (method.getModifiers() == Modifier.PUBLIC && method.getParameterTypes().length == 0 && (name.startsWith("get") || name.startsWith("is")) && containsSetterForGetter(clazz, method)) {
String propertyName;
if (name.startsWith("get")) {
propertyName = Character.toLowerCase(name.charAt(3)) + name.substring(4);
} else if (name.startsWith("is")) {
propertyName = Character.toLowerCase(name.charAt(2)) + name.substring(3);
} else {
throw new PropertyException("method '" + name + "' is not a getter, thereof no setter can be found");
}
try {
Object propertyValue = method.invoke(target);
if (propertyValue != null && propertyValue instanceof Map) {
@SuppressWarnings("unchecked")
Map<String, Object> propertiesContent = getNestedProperties(propertyName, (Map<String, Object>) propertyValue);
properties.putAll(propertiesContent);
} else {
properties.put(propertyName, propertyValue);
}
} catch (IllegalAccessException ex) {
throw new PropertyException("cannot set property '" + propertyName + "' - '" + name + "' is null and cannot be auto-filled", ex);
} catch (InvocationTargetException ex) {
throw new PropertyException("cannot set property '" + propertyName + "' - '" + name + "' is null and cannot be auto-filled", ex);
}
} // if
} // for
return properties;
}
private static boolean containsSetterForGetter(Class<?> clazz, Method method) {
String methodName = method.getName();
String setterName;
if (methodName.startsWith("get")) {
setterName = "set" + methodName.substring(3);
} else if (methodName.startsWith("is")) {
setterName = "set" + methodName.substring(2);
} else {
throw new PropertyException("method '" + methodName + "' is not a getter, thereof no setter can be found");
}
Method[] methods = clazz.getMethods();
for (Method m : methods) {
if (m.getName().equals(setterName)) {
return true;
}
}
return false;
}
/**
* Get a direct or indirect property (dotted property: prop1.prop2.prop3) on the target object.
* @param target the target object from which to get the property.
* @param propertyName the name of the property to get.
* @return the value of the specified property.
* @throws PropertyException if an error happened while trying to get the property.
*/
public static Object getProperty(Object target, String propertyName) throws PropertyException {
String[] propertyNames = propertyName.split("\\.");
Object currentTarget = target;
for (int i = 0; i < propertyNames.length; i++) {
String name = propertyNames[i];
Object result = callGetter(currentTarget, name);
if (result == null && i < propertyNames.length -1) {
throw new PropertyException("cannot get property '" + propertyName + "' - '" + name + "' is null");
}
currentTarget = result;
}
return currentTarget;
}
/**
* Set a {@link Map} of direct or indirect properties on the target object.
* @param target the target object on which to set the properties.
* @param properties a {@link Map} of String/Object pairs.
* @throws PropertyException if an error happened while trying to set a property.
*/
public static void setProperties(Object target, Map<String, Object> properties) throws PropertyException {
for (Map.Entry<String, Object> entry : properties.entrySet()) {
String name = entry.getKey();
Object value = entry.getValue();
setProperty(target, name, value);
}
}
/**
* Return a comma-separated String of r/w properties of the specified object.
* @param obj the object to introspect.
* @return a a comma-separated String of r/w properties.
*/
public static String propertiesToString(Object obj) {
StringBuilder sb = new StringBuilder();
Map<String, Object> properties = new TreeMap<String, Object>(getProperties(obj));
Iterator<String> it = properties.keySet().iterator();
while (it.hasNext()) {
String property = it.next();
Object val = getProperty(obj, property);
sb.append(property);
sb.append("=");
sb.append(val);
if (it.hasNext()) {
sb.append(", ");
}
}
return sb.toString();
}
/**
* Set a direct property on the target object. Conversions from propertyValue to the proper destination type
* are performed whenever possible.
* @param target the target object on which to set the property.
* @param propertyName the name of the property to set.
* @param propertyValue the value of the property to set.
* @throws PropertyException if an error happened while trying to set the property.
*/
private static void setDirectProperty(Object target, String propertyName, Object propertyValue) throws PropertyException {
Method setter = getSetter(target, propertyName);
Class<?> parameterType = setter.getParameterTypes()[0];
try {
if (propertyValue != null) {
Object transformedPropertyValue = transform(propertyValue, parameterType);
setter.invoke(target, transformedPropertyValue);
} else {
setter.invoke(target);
}
} catch (IllegalAccessException ex) {
throw new PropertyException("property '" + propertyName + "' is not accessible", ex);
} catch (InvocationTargetException ex) {
throw new PropertyException("property '" + propertyName + "' access threw an exception", ex);
}
}
private static Map<String, Object> getNestedProperties(String prefix, Map<String, Object> properties) {
Map<String, Object> result = new HashMap<String, Object>();
for (Map.Entry<String, Object> entry : properties.entrySet()) {
String name = entry.getKey();
String value = (String) entry.getValue();
result.put(prefix + '.' + name, value);
}
return result;
}
private static Object transform(Object value, Class<?> destinationClass) {
if (value.getClass() == destinationClass) {
return value;
}
if ( value.getClass() == boolean.class || value.getClass() == Boolean.class ||
value.getClass() == byte.class || value.getClass() == Byte.class ||
value.getClass() == short.class || value.getClass() == Short.class ||
value.getClass() == int.class || value.getClass() == Integer.class ||
value.getClass() == long.class || value.getClass() == Long.class ||
value.getClass() == float.class || value.getClass() == Float.class ||
value.getClass() == double.class || value.getClass() == Double.class
) {
return value;
}
if ((destinationClass == boolean.class || destinationClass == Boolean.class) && value.getClass() == String.class) {
return Boolean.valueOf((String) value);
}
if ((destinationClass == byte.class || destinationClass == Byte.class) && value.getClass() == String.class) {
return new Byte((String) value);
}
if ((destinationClass == short.class || destinationClass == Short.class) && value.getClass() == String.class) {
return new Short((String) value);
}
if ((destinationClass == int.class || destinationClass == Integer.class) && value.getClass() == String.class) {
return new Integer((String) value);
}
if ((destinationClass == long.class || destinationClass == Long.class) && value.getClass() == String.class) {
return new Long((String) value);
}
if ((destinationClass == float.class || destinationClass == Float.class) && value.getClass() == String.class) {
return new Float((String) value);
}
if ((destinationClass == double.class || destinationClass == Double.class) && value.getClass() == String.class) {
return new Double((String) value);
}
throw new PropertyException("cannot convert values of type '" + value.getClass().getName() + "' into type '" + destinationClass + "'");
}
private static void callSetter(Object target, String propertyName, Object parameter) throws PropertyException {
Method setter = getSetter(target, propertyName);
try {
setter.invoke(target, parameter);
} catch (IllegalAccessException ex) {
throw new PropertyException("property '" + propertyName + "' is not accessible", ex);
} catch (InvocationTargetException ex) {
throw new PropertyException("property '" + propertyName + "' access threw an exception", ex);
}
}
private static Object callGetter(Object target, String propertyName) throws PropertyException {
Method getter = getGetter(target, propertyName);
try {
return getter.invoke(target);
} catch (IllegalAccessException ex) {
throw new PropertyException("property '" + propertyName + "' is not accessible", ex);
} catch (InvocationTargetException ex) {
throw new PropertyException("property '" + propertyName + "' access threw an exception", ex);
}
}
private static Method getSetter(Object target, String propertyName) {
if (propertyName == null || "".equals(propertyName)) {
throw new PropertyException("encountered invalid null or empty property name");
}
String setterName = "set" + propertyName.substring(0, 1).toUpperCase() + propertyName.substring(1);
Method[] methods = target.getClass().getMethods();
for (Method method : methods) {
if (method.getName().equals(setterName) && method.getReturnType().equals(void.class) && method.getParameterTypes().length == 1) {
return method;
}
}
throw new PropertyException("no writeable property '" + propertyName + "' in class '" + target.getClass().getName() + "'");
}
private static Method getGetter(Object target, String propertyName) {
String getterName = "get" + propertyName.substring(0, 1).toUpperCase() + propertyName.substring(1);
String getterIsName = "is" + propertyName.substring(0, 1).toUpperCase() + propertyName.substring(1);
Method[] methods = target.getClass().getMethods();
for (Method method : methods) {
if ((method.getName().equals(getterName) || method.getName().equals(getterIsName)) && !method.getReturnType().equals(void.class) && method.getParameterTypes().length == 0) {
return method;
}
}
throw new PropertyException("no readable property '" + propertyName + "' in class '" + target.getClass().getName() + "'");
}
private static Class<?> getPropertyType(Object target, String propertyName) {
String getterName = "get" + propertyName.substring(0, 1).toUpperCase() + propertyName.substring(1);
String getterIsName = "is" + propertyName.substring(0, 1).toUpperCase() + propertyName.substring(1);
Method[] methods = target.getClass().getMethods();
for (Method method : methods) {
if ((method.getName().equals(getterName) || method.getName().equals(getterIsName)) && !method.getReturnType().equals(void.class) && method.getParameterTypes().length == 0) {
return method.getReturnType();
}
}
throw new PropertyException("no property '" + propertyName + "' in class '" + target.getClass().getName() + "'");
}
}