Java从入门到精通 - 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("**************");
  }
 }

}