使用反射设置对象属性

Question

我按名称获取类,我需要使用相应的数据更新它们,我的问题是如何使用java我想要添加方法一些虚拟数据.我不知道类类型我只是获取类名并使用反射来获取他的数据

我使用此代码来获取类实例和

Class<?> classHandle = Class.forName(className);

Object myObject = classHandle.newInstance();

// iterate through all the methods declared by the class
for (Method method : classHandle.getMethods()) {
    // find all the set methods
    if (method.getName().matches("set[A-Z].*")

并且知道我找到了我想用数据更新它的set方法的列表我该怎么做.

假设在类名中我得到了人,而且类有setSalary和setFirstName等我怎样才能用反射设置它们？

public class Person {

    public void setSalery(double salery) {
        this.salery = salery;
    }

    public void setFirstName(String FirstName) {
        this.FirstName = FirstName;
    }   
}

Answer 1

您也可以使用反射直接将值设置为属性,而不是尝试调用setter.例如:

public static boolean set(Object object, String fieldName, Object fieldValue) {
    Class<?> clazz = object.getClass();
    while (clazz != null) {
        try {
            Field field = clazz.getDeclaredField(fieldName);
            field.setAccessible(true);
            field.set(object, fieldValue);
            return true;
        } catch (NoSuchFieldException e) {
            clazz = clazz.getSuperclass();
        } catch (Exception e) {
            throw new IllegalStateException(e);
        }
    }
    return false;
}

呼叫:

Class<?> clazz = Class.forName(className);
Object instance = clazz.newInstance();
set(instance, "salary", 15);
set(instance, "firstname", "John");

仅供参考,这是等效的通用吸气剂:

@SuppressWarnings("unchecked")
public static <V> V get(Object object, String fieldName) {
    Class<?> clazz = object.getClass();
    while (clazz != null) {
        try {
            Field field = clazz.getDeclaredField(fieldName);
            field.setAccessible(true);
            return (V) field.get(object);
        } catch (NoSuchFieldException e) {
            clazz = clazz.getSuperclass();
        } catch (Exception e) {
            throw new IllegalStateException(e);
        }
    }
    return null;
}

呼叫:

Class<?> clazz = Class.forName(className);
Object instance = clazz.newInstance();
int salary = get(instance, "salary");
String firstname = get(instance, "firstname");

Answer 2

if (method.getName().matches("set[A-Z].*") {
  method.invoke(person,salary)
  // and so on
}

了解您可以method.getPagetParameterTypes() 根据结果发出的参数构建您的参数并提供。