The usage and efficiency of beanutils.copyproperties () method

1.BeanUtils provides packaging for the Java reflection and introspection APIs. Its main purpose is to use the reflection mechanism to deal with the properties of JavaBean. The Po object and the Vo object that we often use in the project have the same properties in many cases, and the Beanutils.copyproperties () method can reduce the programmer's Get/set method again, beanutils.copyproperties

() method also has its advantages and disadvantages, below we through the program to verify.

2. First we create two classes: Studen.java and Studentvo.java two Student.java package my.test;

public class Student {private Integer ID;

Private String sname;

Private String spwd;

Private String saddress;

Public Integer GetId () {return id;

The public void SetId (Integer id) {this.id = ID;

Public String Getsname () {return sname;

} public void Setsname (String sname) {this.sname = sname;

Public String getspwd () {return spwd;

} public void Setspwd (String spwd) {this.spwd = spwd;

Public String getsaddress () {return saddress;

} public void Setsaddress (String saddress) {this.saddress = saddress;

}} Studentvo.java package my.test;

public class Studentvo {private Integer ID;

Private String sname;

Private String spwd;

Private String saddress; Public IntegerGetId () {return id;

The public void SetId (Integer id) {this.id = ID;

Public String Getsname () {return sname;

} public void Setsname (String sname) {this.sname = sname;

Public String getspwd () {return spwd;

} public void Setspwd (String spwd) {this.spwd = spwd;

Public String getsaddress () {return saddress;

} public void Setsaddress (String saddress) {this.saddress = saddress;

}

}

You can see that these two classes have the same properties

Test.java

Package my.test;

Import java.lang.reflect.InvocationTargetException;

Import Org.apache.commons.beanutils.BeanUtils;

public class Test {public static void main (string[] args) {Student stu = new Student ();

Stu.setid (2);

Stu.setsname ("Zhangsan");

Stu.setsaddress ("Shanghai");

Stu.setspwd ("QWEASD");

Studentvo Stuvo = new Studentvo ();

Long start = System.currenttimemillis ();

Stuvo.setid (Stu.getid ());

Stuvo.setsname (Stu.getsname ());

Stuvo.setspwd (Stu.getspwd ());

Stuvo.setsaddress (Stu.getsaddress ());

Long end = System.currenttimemillis ();

Long time2 = End-start;

SYSTEM.OUT.PRINTLN ("The result of using the Get/set method:");

System.out.println (time2 + "MS");

System.out.println (Stuvo.getid ());

System.out.println (Stuvo.getsname ());

System.out.println (Stuvo.getspwd ());

System.out.println (Stuvo.getsaddress ());

System.out.println ("----------------------");

Long time1 = usecoryproperties (Stuvo, Stu);

SYSTEM.OUT.PRINTLN ("Use the result of the Beanutils.copyproperties () method:"); System.Out.println (time1 + "MS");

System.out.println (Stuvo.getid ());

System.out.println (Stuvo.getsname ());

System.out.println (Stuvo.getspwd ());

System.out.println (Stuvo.getsaddress ());

System.out.println (Stuvo.getdate ());

private static long Usecoryproperties (object A, object B) {Long start = System.currenttimemillis ();

try {beanutils.copyproperties (A, b);

catch (Illegalaccessexception e) {//TODO auto-generated catch block E.printstacktrace ();

catch (InvocationTargetException e) {//TODO auto-generated catch block E.printstacktrace ();

Long end = System.currenttimemillis ();

return end-start;

}

}

Output results:

Results of using the Get/set method:

0ms

2

zhangsan

qweasd

Shanghai

----------------------

Results of using the Beanutils.copyproperties () method:

93ms

2

zhangsan

QWEASD

We can see from the result that the Beanutils.copyproperties () method can be used to copy the properties of the student class, and also to obtain the values of the set.

But we see the low efficiency, the use of the Get/set method basically does not consume time, but the use of the Beanutils.copyproperties () method is time-consuming to achieve

99MS, this only sets a few attributes, can be learned that when the number of attributes more and more time will be more and more consumption, but it saves manual operation.

Limitations of the 3.beanutils.copyproperties () method

Processing is done only when the properties of the two classes are the same, not for the different properties, not for the Java.util.Date class, but for the java.sql.Date, and for the Integer,boolean,long type.

The default value is NULL, but the default value is 0 after the method is used, so be careful. Use is also relatively low efficiency, so be cautious to use. When two classes are together this method does not, as follows

  Class studentvo{...  

  }  

  Class student{...  

  }  

   

  public class Test {public  

      static void Main (string[] args) {  

          ...  

      }  

  }  

4. Jar Package Required

Commons-beanutils-*.jar

Commons-logging-*.jar