java从入门到精髓 - 反射Field

import java.lang.reflect.Field;
public class FieldTest {

    int i;
    public float f;
    protected boolean b;
    private String s;
    
    public FieldTest()
    {
        i=0;
        f=0.0f;
        b = true;
        s = "";
    }
    public static void main(String[] args){
        //进行类实例化：
        FieldTest fieldTest = new FieldTest();
        
        Field[] declaredFields = FieldTest.class.getDeclaredFields();
        for(int i=0;i<declaredFields.length;i++){
            Field field = declaredFields[i];
            System.out.println("名称为："+field.getName());
            Class fieldType = field.getType();
            System.out.println("类型为："+field.getType());
            boolean isTurn = true;
            while(isTurn)
            {
                try{
                    isTurn = false;
                    System.out.println("修改前的值为："+ field.get(fieldTest));
                    if(fieldType.equals(int.class))
                    {
                        System.out.println("利用setInt()方法修改成员变量的值.");
                        field.setInt(fieldTest, 124);
                    }
                    else if(fieldType.equals(float.class))
                    {
                        System.out.println("利用setFloat()方法修改成员变量的值.");
                        field.setFloat(fieldTest, 9.9f);
                    }else if(fieldType.equals(boolean.class))
                    {
                        System.out.println("利用setBoolean()方法修改成员变量的值.");
                        field.setBoolean(fieldTest, false);
                    }
                    else
                    {
                        System.out.println("利用set()方法修改成员变量的值.");
                        field.set(fieldTest, "NWQ");
                    }
                    System.out.println("修改后的值为："+field.get(fieldTest));
                }catch(Exception e)
                {
                    System.out.println("在设置成员变量时发生异常,执行setAccessible()方法.");
                    field.setAccessible(true);
                    isTurn = true;
                }
            }
            System.out.println("**************");
        }
    }
}