//问题如下:
public class Users {
private String UserID;
private String UserName;
public String getUserName() {
return this.UserName;
}
public void setUserName(String userName) {
this.UserName = userName;
}
public String getUserID() {
return this.UserID;
}
public void setUserID(String userID) {
this.UserID = userID;
}
//提供类名称,方法名称,以及方法中参数的值,能否通过反射,执行某个方法?
//例如动态的执行“Users”类的“setUserID”方法,将this.UserID的值 设置为“administrator”?
public void execute(String ClassName,String MethodName,String ParameterValue)
{
}
}
public class Users {
private String UserID;
private String UserName;
public String getUserName() {
return this.UserName;
}
public void setUserName(String userName) {
this.UserName = userName;
}
public String getUserID() {
return this.UserID;
}
public void setUserID(String userID) {
this.UserID = userID;
}
//提供类名称,方法名称,以及方法中参数的值,能否通过反射,执行某个方法?
//例如动态的执行“Users”类的“setUserID”方法,将this.UserID的值 设置为“administrator”?
public void execute(String ClassName,String MethodName,String ParameterValue)
{
}
}
* Invokes accessible method of an object.
*
* @param c class that contains method
* @param obj object to execute
* @param method method to invoke
* @param paramClasses classes of parameters
* @param params parameters
� */
public static Object invoke(Class c, Object obj, String method, Class[] paramClasses, Object[] params) throws IllegalAccessException, NoSuchMethodException, InvocationTargetException {
Method m = c.getMethod(method, paramClasses);
return m.invoke(obj, params);
}在不知道参数类型的情况下:
/**
* Returns classes from array of specified objects.
*/
public static Class[] getClasses(Object... objects) {
if (objects == null) {
return null;
}
Class[] result = new Class[objects.length];
for (int i = 0; i < objects.length; i++) {
if (objects[i] != null) {
result[i] = objects[i].getClass();
}
}
return result;
}
/**
* Invokes accessible method of an object without specifying parameter types.
* @param obj object
* @param method method of an object
* @param params method parameters
*/
public static Object invoke(Object obj, String method, Object[] params) throws IllegalAccessException, NoSuchMethodException, InvocationTargetException {
Class[] paramClass = getClasses(params);
return invoke(obj, method, paramClass, params);
}
写了一段例子,希望对你有帮助public class Test {
public static void main(String[] args) throws Exception{
List list = new ArrayList();
Class c = Class.forName("java.util.ArrayList");
Method method = c.getDeclaredMethod("add", new Class[]{Object.class});
method.invoke(list, new Object[]{new Integer(100)});
System.out.println(list.get(0));
}
}
private String UserName; public String getUserName() {
return this.UserName;
} public void setUserName(String userName) {
this.UserName = userName;
} public String getUserID() {
return this.UserID;
} public void setUserID(String userID) {
this.UserID = userID;
}}import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;public class Test { public static void main(String[] args) {
Test test = new Test();
Users user = new Users();
test.execute(user, "Users", "setUserName", "张三");
// 通过反射已经设置了Users对象的userName属性为张三,下面打印
System.out.println(user.getUserName());
} /**
*
* @param obj
* 待执行方法的对象
* @param ClassName
* 待执行方法对象的类
* @param MethodName
* 待执行的方法名
* @param ParameterValue
* 待执行方法的参数
*/
public void execute(Object obj, String ClassName, String MethodName,
String ParameterValue) {
Class cls = null;
try {
cls = Class.forName(ClassName);
} catch (ClassNotFoundException e) {
// 通过ClassName反射获取该类失败
e.printStackTrace();
}
Method method = null;
try {
method = cls.getMethod(MethodName, String.class);
} catch (SecurityException e) {
// 通过MethodName反射获取该方法失败,SecurityManager校验失败
e.printStackTrace();
} catch (NoSuchMethodException e) {
// 通过MethodName反射获取该方法失败,该方法不存在
e.printStackTrace();
}
try {
method.invoke(obj, ParameterValue);
} catch (IllegalArgumentException e) {
// 反射执行该方法失败,参数不正确
e.printStackTrace();
} catch (IllegalAccessException e) {
// 反射执行该方法失败,无法执行
e.printStackTrace();
} catch (InvocationTargetException e) {
// 反射执行该方法失败,该方法本身抛出异常
e.printStackTrace();
}
}}