Search method in Struts with MySQL - struts2

Question

Hey guys I'm having some problems with a project that I'm doing :/
I have this code
public class ListaAlumnoAction {
private List<Alumno> alumnos;
public String execute(){
String camino="success";
EntityManager em= Utilitario.getInstance().getEntityManager();
Query query=em.createQuery("Select o From Alumno o");
alumnos=query.getResultList();
return camino;
}
public List<Alumno> getAlumnos() {
return alumnos;
}
public void setAlumnos(List<Alumno> alumnos) {
this.alumnos = alumnos;
}
}
This method gives me a list of students. But in this case I just want 1 student, searching by code for example or by name and last name. The thing is I don't know what kind of tools use for this purpose.
Thanks in advanced.

Answer 1

For searching the student by specified input criteria, you are in need of passing the required input from the page to the action class. And need to modify the query which will search the student record by mentioned name or last name or desired input.
For example, assume student name is the input criteria
To pass the student name from the page:
<s:form>
......
<s:textfield name="studentName" label="Student Name"></s:textfield>
<s:submit value="Search" name="submit" action="ListaAlumnoAction"/>
......
</s:form>
Here the studentName will be the input for search operation and ListaAlumnoAction is action which will fired when Search button clicked.
To get the Student Name in the Action Class:
public class ListaAlumnoAction {
private List<Alumno> alumnos;
/* Please note both the text filed name in the page and attribute should be same "studentName" */
private String studentName;
public String execute(){
String camino="success";
EntityManager em= Utilitario.getInstance().getEntityManager();
// "name" variable will hold the studentName
String name = getStudentName();
// Modify the query, by passing the name if it is not null
Query query=em.createQuery("Select o From Alumno o");
alumnos=query.getResultList();
return camino;
}
public List<Alumno> getAlumnos() {
return alumnos;
}
public void setAlumnos(List<Alumno> alumnos) {
this.alumnos = alumnos;
}
// getter and setter for the studentName
public String getStudentName(){
return studentName;
}
public void setStudentName(String studentName){
this.studentName = studentName;
}
}