反射

public class PrivateTest {
    private String name = "hello";
    public String getName() {
        return name;
    }
}

public class RefectionTest {

    public static void main(String[] args) throws Exception {

        PrivateTest pt = new PrivateTest();

        Class<PrivateTest> classz = PrivateTest.class;

        Field field = classz.getDeclaredField("name");
        field.setAccessible(true); //默认是false, false表示被反射的对象应该执行Java语言访问检查。

        field.set(pt, "jimmy");

        System.out.println(pt.getName()); //jimmy

    }
}