We will learn how to create a Web application using Struts 1 and Web service. A case study will be illustrated as follow:
- a Web server running on Tomcat server.
- a Web page enabling user to enter two numbers and click submit to the server
- the server receives two numbers, then calls a Web service to calculate the sum of the two numbers. And then displays the results in another page.
Config Tomcat server for a Web service
You could see in the topic: service-oriented programming with web service
- Step 1: Download Tomcat server from Apache site: http://tomcat.apache.org/download-70.cgi (version 6.0 and higher)
- Step 2: Download web service (AXIS) library of Apache: http://axis.apache.org/axis/
- Step 3: unzip the axis folder, copy axis folder into Tomcat\webapps. And then copy xerces.jar from Tomcat\common\lib into Tomcat\webapps\axis\WEB-INF\lib
- Step 4: setup your environment variables:
JAVA_HOME = absolute path to your java root directory
AXIS_HOME = absolute path to your unzipped axis folder
CATALINA_HOME = absolute path to your Tomcat folder
DEPLOY_HOME = {CATALINA_HOME}\webapps\axis\WEB-INF\lib
Create a Web service
- Step 5: Go to the directory: \Tomcat\webapps\axis, create a file named Calculators.jws with this content:
public class Calculators{
public String Add(double x, double y){
return (x+y)+"";
}
public String Sub(double x, double y){
return (x-y)+"";
}
public String Mul(double x, double y){
return (x*y)+"";
}
public String Div(double x, double y){
return (x/y)+"";
}
}
- Step 6: Verifying your Web service by running Tomcat server (run the file Tomcat\bin\startup.bat), then running your web browser and typing the URL into address bar:
http://localhost:8080/axis/Calculators.jws?wsdl
If this content appears, your Web service is well created!
Config and development a Web application using Struts 1 framework and Web service
- Step 1: Go to the Tomcat/webapps folder, create a web folder (strutCalculator) with a WEB-INF sub folder. In which, download the struts 1 lib into WEB-INF/lib folder:
link to download Struts 1 lib:http://mirrors.digipower.vn/apache//struts/library/struts-1.3.10-lib.zip
- Step 2: Go to the WEB-INF/src folder, create a Java project with two packages: control, entity. And then code them as:
entity.Calculator.java
package entity;
import javax.servlet.http.HttpServletRequest;
import org.apache.struts.action.ActionErrors;
import org.apache.struts.action.ActionMapping;
import org.apache.struts.action.ActionMessage;
public class Calculator extends org.apache.struts.action.ActionForm{
private String firstnumber;
private String secondnumber;
private String result;
public Calculator(){
super();
}
public Calculator(String a, String b){
super();
firstnumber = a;
secondnumber = b;
}
public String getFirstnumber() {
return firstnumber;
}
public void setFirstnumber(String firstnumber) {
this.firstnumber = firstnumber;
}
public String getSecondnumber() {
return secondnumber;
}
public void setSecondnumber(String secondnumber) {
this.secondnumber = secondnumber;
}
public String getResult() {
return result;
}
public void setResult(String result) {
this.result = result;
}
public ActionErrors validate(ActionMapping mapping, HttpServletRequest request) {
ActionErrors errors = new ActionErrors();
if (firstnumber == null || firstnumber.length() < 1) {
errors.add("firstnumber", new ActionMessage("error.firstnumber.required"));
}else {
try{
Double.parseDouble(firstnumber);
}catch(Exception e){
errors.add("firstnumber", new ActionMessage("error.firstnumber.double"));
}
}
if (secondnumber == null || secondnumber.length() < 1) {
errors.add("secondnumber", new ActionMessage("error.secondnumber.required"));
}else {
try{
Double.parseDouble(secondnumber);
}catch(Exception e){
errors.add("secondnumber", new ActionMessage("error.secondnumber.double"));
}
}
return errors;
}
}
control.CalculatorCtr.java
package control;
import org.apache.axis.client.Service;
import org.apache.axis.client.Call;
import org.apache.axis.encoding.XMLType;
import javax.xml.rpc.ParameterMode;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import org.apache.struts.action.ActionForm;
import org.apache.struts.action.ActionMapping;
import org.apache.struts.action.ActionForward;
public class CalculatorCtr extends org.apache.struts.action.Action{
private final static String RESULT = "result";
public entity.Calculator calculate(String methodName, entity.Calculator cal){
String endpointURL="http://localhost:8080/axis/Calculator.jws";
Service service=new Service();
try{
Call call=(Call)service.createCall();
call.setTargetEndpointAddress(new java.net.URL(endpointURL));
call.setOperationName(methodName);
call.addParameter("a", XMLType.XSD_DOUBLE, ParameterMode.PARAM_MODE_IN);
call.addParameter("b", XMLType.XSD_DOUBLE, ParameterMode.PARAM_MODE_IN);
String result=(String)call.invoke(new Object[]{Double.parseDouble(cal.getFirstnumber()),Double.parseDouble(cal.getSecondnumber())});
cal.setResult(result);
}catch(Exception ex){
System.out.println("Error: "+ex);
}
return cal;
}
public ActionForward execute(ActionMapping mapping, ActionForm form,
HttpServletRequest request, HttpServletResponse response)
throws Exception {
entity.Calculator calculator = (entity.Calculator) form;
form = calculate("Add", calculator);
return mapping.findForward(RESULT);
}
}
After compiling these packages, copy the .class files (including their packages) into the WEB-INF/classes folder.
- Step 3: Return to the Web root directory, create three files .jsp as follow:
add.jsp
<%@page contentType="text/html" pageEncoding="UTF-8"%>
<%@taglib uri="/WEB-INF/struts-html.tld" prefix="html" %>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"
"http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>Web service: Add</title>
</head>
<body>
<div style="color:red">
<html:errors />
</div>
<html:form action="/add" >
First number : <html:text name="Calculator" property="firstnumber" /> <br>
Second number : <html:text name="Calculator" property="secondnumber" /> <br>
<html:submit value="Add" />
</html:form>
</body>
</html>
Note that the tags in red are Struts 1 tags, refer from the first line in red.
doAdd.jsp
<%@page contentType="text/html" pageEncoding="UTF-8"%>
<%@taglib uri="/WEB-INF/struts-bean.tld" prefix="bean" %>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"
"http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>Web service: Add result</title>
</head>
<body>
The sum of <bean:write name="Calculator" property="firstnumber"></bean:write>
and <bean:write name="Calculator" property="secondnumber"></bean:write>
is <bean:write name="Calculator" property="result"></bean:write>
</body>
</html>
- Step 4: Go to the WEB-INF folder, copy all .tld and .xml file from Struts 1 lib into this directory as follow:
- Step 5: Edite the file web.xml and struts-config.xml as follow:
web.xml
<?xml version="1.0" encoding="UTF-8"?>
<web-app version="2.5" xmlns="http://java.sun.com/xml/ns/javaee" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd">
<servlet>
<servlet-name>action</servlet-name>
<servlet-class>org.apache.struts.action.ActionServlet</servlet-class>
<init-param>
<param-name>config</param-name>
<param-value>/WEB-INF/struts-config.xml</param-value>
</init-param>
<init-param>
<param-name>debug</param-name>
<param-value>2</param-value>
</init-param>
<init-param>
<param-name>detail</param-name>
<param-value>2</param-value>
</init-param>
<load-on-startup>2</load-on-startup>
</servlet>
<servlet-mapping>
<servlet-name>action</servlet-name>
<url-pattern>*.do</url-pattern>
</servlet-mapping>
<session-config>
<session-timeout>30</session-timeout>
</session-config>
<welcome-file-list>
<welcome-file>add.jsp</welcome-file>
</welcome-file-list>
<jsp-config>
<taglib>
<taglib-uri>/WEB-INF/struts-bean.tld</taglib-uri>
<taglib-location>/WEB-INF/struts-bean.tld</taglib-location>
</taglib>
<taglib>
<taglib-uri>/WEB-INF/struts-html.tld</taglib-uri>
<taglib-location>/WEB-INF/struts-html.tld</taglib-location>
</taglib>
<taglib>
<taglib-uri>/WEB-INF/struts-logic.tld</taglib-uri>
<taglib-location>/WEB-INF/struts-logic.tld</taglib-location>
</taglib>
<taglib>
<taglib-uri>/WEB-INF/struts-nested.tld</taglib-uri>
<taglib-location>/WEB-INF/struts-nested.tld</taglib-location>
</taglib>
<taglib>
<taglib-uri>/WEB-INF/struts-tiles.tld</taglib-uri>
<taglib-location>/WEB-INF/struts-tiles.tld</taglib-location>
</taglib>
</jsp-config>
</web-app>
Note that all texts in red are the content you need to modify to be appropriated to your Web application.
struts-config.xml
<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE struts-config PUBLIC
"-//Apache Software Foundation//DTD Struts Configuration 1.2//EN"
"http://jakarta.apache.org/struts/dtds/struts-config_1_2.dtd">
<struts-config>
<form-beans>
<form-bean name="Caculator" type="entity.Caculator"/>
</form-beans>
<global-exceptions>
</global-exceptions>
<global-forwards>
<forward name="welcome" path="/Welcome.do"/>
</global-forwards>
<action-mappings>
<action input="/add.jsp" name="Caculator" path="/add" scope="session" type="control.CalculatorCtr">
<forward name="result" path="/doAdd.jsp" />
</action>
<action path="/Welcome" forward="/welcomeStruts.jsp"/>
</action-mappings>
<controller processorClass="org.apache.struts.tiles.TilesRequestProcessor"/>
<message-resources parameter="entity/ApplicationResource"/>
<!-- ========================= Tiles plugin ===============================-->
<plug-in className="org.apache.struts.tiles.TilesPlugin" >
<set-property property="definitions-config" value="/WEB-INF/tiles-defs.xml" />
<set-property property="moduleAware" value="true" />
</plug-in>
<!-- ========================= Validator plugin ================================= -->
<plug-in className="org.apache.struts.validator.ValidatorPlugIn">
<set-property
property="pathnames"
value="/WEB-INF/validator-rules.xml,/WEB-INF/validation.xml"/>
</plug-in>
</struts-config>
Note that all texts in red are the content you need to modify to be appropriated to your Web application.
Results
- add welcome page:
- result page:
- when entering incorrect data type:
