update a list of value in textfield in struts2 - struts2

Question

I am facing a problem in Struts2, In my sample application I have Array of objects (Say person name) , I need to display these names as a editable text fields , I am using Iterators for this , I am successful in diaplying, But When I cange the same value and submit the form. I am getting the entire array which holds null value.
Say for Exaple in my form bean I have a property
Name [] names;
In my JSP I have the iterator as
If there are 3 names then I can get these names on the UI if I can initialized them with some dummy value but when I edit and sumbit, then "names" array is not getting updated. Please help me in this regard

Answer 1

In Struts2, when you need to repopulate the list of bean items, you need to refer them through indices. Please refer the example below:
Bean class:
public class Person {
private int id;
private String name;
public int getId() {
return id;
}
public void setId(int id) {
this.id = id;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
}
Action class:
public class PersonAction extends ActionSupport {
private List<Person> persons;
public List<Person> getPersons() {
return persons;
}
public void setPersons(List<Person> persons) {
this.persons = persons;
}
//Initial Load method
#Override
public String execute() {
persons = new ArrayList<Person>();
int alpha = 65;
for(int i = 0; i < 3 ; i++) {
Person person = new Person();
person.setId(i);
person.setName(String.valueOf((char)alpha++));
persons.add(person);
}
return SUCCESS;
}
//Function that handles the form submit
public String updatePerson() {
for(Person person : persons) {
System.out.println(person.getId() + ":" + person.getName());
}
return SUCCESS;
}
}
Page:
<s:form action="doUpdate">
<s:iterator value="persons" status="stat" var="person">
<s:textfield value="%{#person.name}" name="persons[%{#stat.count}].name"/><br/>
</s:iterator>
<s:submit value="Submit"/>
</s:form>
When you submit the above form, the url would look like doUpdate?persons[0].name=A1&persons[1].name=B1&persons[2].name=C1. Similarly if you need to update id of the first person object, you will append persons[0].id=3 to the url using form. In the <s:textfield value="%{#person.name}" name="persons[%{#stat.count}].name"/>, you tell that the predefined value is person's name, for each object. The name attribute is to set the rendered html input element; the name which will be referenced in the url when the form is submitted. You will get a clear idea if you look into the generated html.

Answer 2

Use the iterator tag of struts2, if list is not empty then use :
<s:iterator value="names" status="namesStatus">
<s:property/><br/>
</s:iterator>