Using values returned by a Java Bean's getproperty for further processing

Question

I need to print the even numbers between a given range of numbers. The upper and lower bounds are set using the setters in the bean. Following is the code that I am using:

package com.bean.animesh;

public class classOfBean implements java.io.Serializable {
private int lowerLimit;
private int upperLimit;
public List<Integer> evenList;

public classOfBean() {

}
public int getLowerLimit() {
    return lowerLimit;
}
public int getUpperLimit() {
    return upperLimit;
}
public void setLowerLimit(int lowerLimit) {
    this.lowerLimit = lowerLimit;
}
public void setUpperLimit(int upperLimit) {
    this.upperLimit = upperLimit;
}
public void setEvenList() {
    List<Integer> evenNumbers = new ArrayList<Integer>();
    for (int i = getLowerLimit(); i <= getUpperLimit(); ++i) {
        evenNumbers.add(i);
    }
    this.evenList = Numbers;
}
public List<Integer> getEvenList() {
    return evenList;
}
}

And this is the JSP page:

<jsp:useBean id="evens" class="com.bean.animesh.classOfBean" scope="session">
<jsp:setProperty name="evens" property="lowerLimit" param="lower"/>
<jsp:setProperty name="evens" property="upperLimit" param="upper"/>
<jsp:setProperty name="evens" property="evenList"/>
</jsp:useBean>

<p>Lower Limit: 
    <jsp:getProperty name="evens" property="lowerLimit"/>
</p>

<p>Upper Limit: 
    <jsp:getProperty name="evens" property="upperLimit"/>
</p>

<p>The list:
    <jsp:getProperty name="evens" property="evenList"/>
</p>

lowerLimit and upperLimit are printed correctly, but when I add the code for evenList, I always get this error Can't find a method to write property 'evenList' of type 'java.util.List' in a bean of type 'com.bean.animesh.classOfBean'.

New Edit:

I edited the bean's methods where the method returns a string rather than an integer list. Now I don't get any error but I get null when I print the returned value by the method. How am I supposed the get the list of the even numbers?

public void setEvenList(String evenList) {
    List<Integer> evenNumbers = new ArrayList<Integer>();
    for (int i = getLowerLimit(); i <= getUpperLimit(); ++i) {
        if (i%2 == 0) {
            evenNumbers.add(i);
        }
    }
    String listString = evenNumbers.toString();
    listString = listString.substring(1, (listString.length())-1);
    System.out.println(listString);
    this.evenList = listString;
}
public String getEvenList() {
    return evenList;
}

What am I doing wrong? Are there any alternatives in Java beans to solve this problem?

Answer 1

By changing the bean methods setEvenList and getEvenList return a String rather than an integer list like this:

public void setEvenList(String listString) {
    List<Integer> evenNumbers = new ArrayList<Integer>();
    for (int i = getLowerLimit(); i <= getUpperLimit(); ++i) {
        if (i%2 == 0) {
            evenNumbers.add(i);
        }
    }
    listString = evenNumbers.toString();
    listString = listString.substring(1, (listString.length())-1);
    System.out.println(listString);
    this.evenList = listString;
}
public String getEvenList() {
    return evenList;
}

and making the setProperty and getProperty for the evenList to be like this:

<jsp:setProperty name="evens" property="evenList" value="0"/>
<jsp:getProperty name="evens" property="evenList"/>

will print the required output.

Thanks everyone for your input.

Answer 2

setEvenList must take an argument of the same type that getEvenList returns. This is standard bean practice.