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java 中反射的應用
java 中反射的應用：
1，獲取指定類的所有成員變量，包括父類的成員變量：
/***
* get all field ,including fields in father/super class
*
* @param clazz
* @return
*/
public static List<Field> getAllFields(Class clazz) {
List<Field> fieldsList = new ArrayList<Field>();// return object
if (clazz == null) {
return null;
}
Class superClass = clazz.getSuperclass();// father class
if (superClass.getName().equals(Object.class.getName()))/*
* java.lang.Object
*/{
// System.out.println("no father");
} else {
// System.out.println("has father");
fieldsList.addAll(getAllFields(superClass));// Recursive
}
Field[] fields = clazz.getDeclaredFields();
for (int i = 0; i < fields.length; i++) {
Field field = fields[i];
fieldsList.add(field);
}
return fieldsList;
}
2，設置指定屬性（私有成員變量）的值
/***
*
* @param obj
* @param propertyName
* : property name
* @param propertyValue
* : value of property
* @throws SecurityException
* @throws NoSuchFieldException
* @throws IllegalArgumentException
* @throws IllegalAccessException
*/
public static void setObjectValue(Object obj, String propertyName,
String propertyValue) throws SecurityException,
NoSuchFieldException, IllegalArgumentException,
IllegalAccessException {
if (StringUtils.isEmpty(propertyName)
|| StringUtils.isEmpty(propertyValue)) {
return;
}
Class<?> clazz = obj.getClass();
Field name = clazz.getDeclaredField(propertyName);
name.setAccessible(true);
name.set(obj, propertyValue);
}
3，獲取指定屬性（私有成員變量）的值
/***
*
* @param obj
* @param propertyName :name of property
* @return
* @throws SecurityException
* @throws NoSuchFieldException
* @throws IllegalArgumentException
* @throws IllegalAccessException
*/
public static Object getObjectValue(Object obj, String propertyName)
throws SecurityException, NoSuchFieldException,
IllegalArgumentException, IllegalAccessException {
if (StringUtils.isEmpty(propertyName)) {
return null;
}
Class<?> clazz = obj.getClass();
Field name = clazz.getDeclaredField(propertyName);
name.setAccessible(true);
return name.get(obj);
}
說明：依賴的jar：commons-lang-2.6.jar
最後更新：2017-04-03 16:48:44