基本操作--反射读取数据

[java]代码库

1.
package s0505反射读取属性值;
//好处,不论多少属性,我用13行代码可以代替所有的get语句
public class Student {
	
  private String name;
  private String sex;
  private String  grade;
  private String age;
  
  public Student()
  {}
  


  public Student(String name, String sex, String grade, String age) {
	this.name = name;
	this.sex = sex;
	this.grade = grade;
	this.age = age;
}



public  String get(String s)
  {
	  String value=null;
	  try {
		   //关键代码******************************************************************
		   value=(String)this.getClass().getDeclaredField(s).get(this);// getDeclaredField(xx).get(yy)  得到yy类的xx属性的值
		   //关键代码******************************************************************
		
	} catch (IllegalArgumentException | IllegalAccessException
			| NoSuchFieldException | SecurityException e) {
		e.printStackTrace();
	}
	  return value;
  }
}


2.
package s0505反射读取属性值;

public class Test {
  public static void main(String[] args){
	  Student a=new Student("张三","男","100","29");
	  Student b=new Student("张四","女","99","21");
	  Student c=new Student("张五","男","98","22");
	  
	  
	  System.out.println(a.get("name")+" "+a.get("sex")+" "+a.get("grade")+" "+a.get("age"));
	  System.out.println(b.get("name")+" "+b.get("sex")+" "+b.get("grade")+" "+b.get("age"));
	  System.out.println(c.get("name")+" "+c.get("sex")+" "+c.get("grade")+" "+c.get("age"));

  }
}