I have index.jsp where I have one link,on clicking on that link that page specific action gets called.Now as on the click of this link,I need to display a page with already populated multiselect list along with few input text fields,in the constructor of the action I populated the TransactionBean which will be binded with fields on next page i.e transactionData.jsp. The transactionData.jsp page is getting displayed correctly with populated multiselected list.Now user can select values from multiselect list and can enter dates in text field and will click on click button,so that a bar chart is displayed.
On click on Click button ,I am calling another action ,which also has TransactionBean as its property.In the execute method of this action ,I am trying to access transactionbean with its getter,but it gives me nullpointerexception.I got to know that ,if we are submitting a page which has fields of bean binded ,then on calling action,bean will be instantiaited automatically through interceptors,but seems like something is not correct here
index.jsp
<%@ page language="java" contentType="text/html; charset=ISO-8859-1"
pageEncoding="ISO-8859-1"%>
<%@ taglib prefix="s" uri="/struts-tags"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"
"http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<title>Hello World</title>
</head>
<body>
<s:form action="displayAction.action">
<h1>Hello World</h1>
<a href="<s:url action="displayAction.action"/>">Transaction Chart
</s:form>
</body>
</html>
DisplayAction.java
public class DisplayAction extends ActionSupport {
TransactionBean transactionBean;
public TransactionBean getTransactionBean() {
return transactionBean;
}
public void setTransactionBean(TransactionBean transactionBean) {
this.transactionBean = transactionBean;
}
public String execute(){
return SUCCESS;
}
public DisplayAction(){
System.out.println("Inside Constructor");
List<String> leftChannelsList = new ArrayList<String>();
leftChannelsList.add("Channel1");
leftChannelsList.add("Channel2");
//TransactionBean transactionBean = new TransactionBean();
setTransactionBean(new TransactionBean());
getTransactionBean().setLeftChannelsList(leftChannelsList);
//Transaction Type Dta
List<String> leftTransTypesList = new ArrayList<String>();
leftTransTypesList.add("TransType1");
leftTransTypesList.add("TransType2");
getTransactionBean().setLeftTransTypesList(leftTransTypesList);
}
}
transactionData.jsp
<%@ page language="java" contentType="text/html; charset=ISO-8859-1"
pageEncoding="ISO-8859-1"%>
<%@ taglib prefix="s" uri="/struts-tags"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"
"http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<s:head theme="ajax" debug="true"/>
<title>Hello World</title>
</head>
<body bgcolor="grey">
<s:form action="displayChart.action">
<s:datetimepicker label="Select From" name="transactionBean.fromDate" displayFormat="MM-dd-yy" required="true" /> <s:datetimepicker label="Select To" name="transactionBean.toDate" displayFormat="MM-dd-yy" required="true" />
<s:optiontransferselect
label="Channels"
name="transactionBean.leftChannels"
leftTitle="Unselected Channels"
rightTitle="Selected Channels"
list="transactionBean.leftChannelsList"
multiple="true"
headerKey="-1"
doubleList="transactionBean.rightChannelsList"
doubleName="transactionBean.rightChannels"
doubleHeaderKey="-1"
doubleHeaderValue="Please Select"
/>
<!-- Transaction Types -->
<s:optiontransferselect
label="transaction Types"
name="transactionBean.leftTransTypes"
leftTitle="Unselected Transaction Type"
rightTitle="Selected Transaction Type"
list="transactionBean.leftTransTypesList"
multiple="true"
headerKey="-1"
doubleList="transactionBean.rightTransTypesList"
doubleName="transactionBean.rightTransTypes"
doubleHeaderKey="-1"
doubleHeaderValue="Please Select"
/>
<s:submit value="click" align="center"/>
</s:form>
</body>
</html>
JfreeChartAction.java
public class JfreeChartAction extends ActionSupport {
private JFreeChart chart;
private TransactionBean transactionBean;
private TransactionDao transactionDao;
public TransactionDao getTransactionDao() {
return transactionDao;
}
public void setTransactionDao(TransactionDao transactionDao) {
this.transactionDao = transactionDao;
}
public TransactionBean getTransactionBean() {
return transactionBean;
}
public void setTransactionBean(TransactionBean transactionBean) {
this.transactionBean = transactionBean;
}
// This method will get called if we specify <param name="value">chart</param>
public JFreeChart getChart() {
return chart;
}
public void setChart(JFreeChart chart) {
this.chart = chart;
}
public JfreeChartAction(){
}
public String execute() throws Exception {
System.out.println("Inside Execute: Start");
System.out.println("From date:"+getTransactionBean().getFromDate());
System.out.println("From date:"+getTransactionBean().getToDate());
System.out.println("leftChannelsList:"+getTransactionBean().getLeftChannelsList());
System.out.println("Left Trans type List"+getTransactionBean().getLeftTransTypesList());
DefaultCategoryDataset dataSet = new DefaultCategoryDataset();
dataSet.setValue(0,"01-04-2014","Channel1");
dataSet.setValue(15000,"01-04-2014","Channel2");
dataSet.setValue(9000,"01-05-2014","Channel1");
dataSet.setValue(1500,"01-05-2014","Channel2");
dataSet.setValue(10000,"01-06-2014","Channel1");
dataSet.setValue(8000,"01-06-2014","Channel2");
chart = ChartFactory.createBarChart(
"Demo Bar Chart", //Chart title
"Mobile Manufacturer", //Domain axis label
"TRANSACTIONS", //Range axis label
dataSet, //Chart Data
PlotOrientation.VERTICAL, // orientation
true, // include legend?
true, // include tooltips?
false // include URLs?
);
chart.setBorderVisible(true);
System.out.println("Inside Execute: End");
return SUCCESS;
}
}
Struts.xml
<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE struts PUBLIC
"-//Apache Software Foundation//DTD Struts Configuration 2.0//EN"
"http://struts.apache.org/dtds/struts-2.0.dtd">
<struts>
<package name="default" namespace="/" extends="struts-default">
<action name="displayAction"
class="com.tutorialspoint.struts2.DisplayAction"
method="execute">
<result name="success">transactionsData.jsp</result>
</action>
</package>
<package name="defaultJfreeChart" namespace="/" extends="jfreechart-default">
<action name="displayChart"
class="com.tutorialspoint.struts2.JfreeChartAction"
method="execute">
<result name="success" type="chart">
<param name="value">chart</param>
<param name="type">jpeg</param>
<param name="width">600</param>
<param name="height">400</param>
</result>
</action>
</package>
</struts>
