什么是反射
获取class文件对象的方式
Object类的getClass()方法
数据类型的静态属性class
Class类中的静态方法
public static Class forName(String className)
// 方式1
Person p = new Person();
Class c = p.getClass();
Person p2 = new Person();
Class c2 = p2.getClass();
System.out.println(p == p2);// false
System.out.println(c == c2);// true
// 方式2
Class c3 = Person.class;
// int.class;
// String.class;
System.out.println(c == c3);
// 方式3
// ClassNotFoundException
Class c4 = Class.forName("renxixao.Person");
System.out.println(c == c4); } }
通过反射获取构造方法并使用
public class Person {
private String name;
int age;
public String address;
public Person() {
}
private Person(String name) {
this.name = name;
}
Person(String name, int age) {
this.name = name;
this.age = age;
}
public Person(String name, int age, String address) {
this.name = name;
this.age = age;
this.address = address;
}
public void show() {
System.out.println("show");
}
public void method(String s) {
System.out.println("method " + s);
}
public String getString(String s, int i) {
return s + "---" + i;
}
private void function() {
System.out.println("function");
}
@Override
public String toString() {
return "Person [name=" + name + ", age=" + age + ", address=" + address
+ "]";
}
}
/*
* 通过反射获取构造方法并使用。
*/
public class ReflectDemo {
public static void main(String[] args) throws Exception {
// 获取字节码文件对象
Class c = Class.forName("renxixao.Person");
// public Constructor[] getConstructors():所有公共构造方法
Constructor[] constructors = c.getConstructors();
for (Constructor con : constructors) {
System.out.println("公共构造方法:"+con);
}
// public Constructor[] getDeclaredConstructors():所有构造方法
Constructor[] declaredConstructors = c.getConstructors();
for (Constructor con : declaredConstructors) {
System.out.println("所有构造方法:"+con);
}
&nbs