Introduction to the use of Apache Commons toolset

Http://developer.51cto.com/art/201511/496849.htm

The Apache Commons contains a number of open source tools for solving problems that are often encountered in programming and reducing duplication of effort. I chose some more commonly used items to do a brief introduction. The article used a lot of online ready-made things, I just did a summary of the finishing.

First, Commons beanutils

Http://jakarta.apache.org/commons/beanutils/index.html

Description: A tool set for the bean. Since beans tend to have a bunch of get and set compositions, Beanutils also makes some packaging on this basis.

Use examples: There are many features, detailed on the Web site. A more common feature is bean copy, which is the property of the copy bean. It would be used if you were developing a layered architecture, such as copying data from PO (persistent object) to Vo (Value object).

The traditional methods are as follows:

Get Teacherform teacherform teacherform= (teacherform) Form;    Construct Teacher Object Teacher teacher=new Teacher ();  Assigned Value Teacher.setname (Teacherform.getname ());  Teacher.setage (Teacherform.getage ());  Teacher.setgender (Teacherform.getgender ());  Teacher.setmajor (Teacherform.getmajor ());    Teacher.setdepartment (Teacherform.getdepartment ());  Persisting teacher object to database hibernatedao=; Hibernatedao.save (teacher);

With Beanutils, the code has changed dramatically, as follows:

Get Teacherform teacherform teacherform= (teacherform) Form;    Construct Teacher Object Teacher teacher=new Teacher ();    The assigned value beanutils.copyproperties (teacher,teacherform);  Persisting teacher object to database hibernatedao=; Hibernatedao.save (teacher);

Ii. Commons CLI

Http://jakarta.apache.org/commons/cli/index.html

Description: This is a tool for processing commands. For example, the main method input string[] needs parsing. You can define the rules of the parameters in advance, and then you can invoke the CLI to resolve them.

Use examples:

 create Options object  options options = new options (); //  add t option, option is the command parameter, false  indicates that // this parameter is not required.    Options.addoption ("T", false,  "Display current time");  options.addoption ("C",  true,  "Country code");    Commandlineparser parser = new posixparser ();   Commandline cmd = parser.parse ( options, args);    if (cmd.hasOption ("T" )  {     // print the date and time }else {     // print the date }   // get c option value   String countrycode = cmd.getoptionvalue ("C");    if (countrycode == null )  {      // print default date }else {      //  print date for country specified by countryCode } 

Third, Commons Codec

Http://jakarta.apache.org/commons/codec/index.html

Description: This tool is used to encode and decode, including Base64,url,soundx and so on. People with this tool should be very clear about this, I will not introduce more.

Iv. Commons Collections

http://jakarta.apache.org/commons/collections/

Description: You can think of this tool as a java.util extension.

Use example: To give a simple example

Orderedmap map = new Linkedmap ();  Map.put ("FIVE", "5");  Map.put ("SIX", "6"); Map.put ("SEVEN", "7");