LinkedList && Servlet

Question

`我是一個新的java和servlet主題。 我寫了一個小的web應用程序。它從Web表單收集一些數據並將其添加到LinkedList中。 但我的調試器顯示我添加到LL不會發生。請幫助！

這裏是一些代碼：

protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { 
    String name = request.getParameter("name"); 
    String surname = request.getParameter("surname"); 
    String fatherName = request.getParameter("fathername"); 
    String department = request.getParameter("department").toLowerCase(); 
    Integer age = Integer.valueOf(request.getParameter("age")); 

    System.out.println(name); 
    System.out.println(surname); 
    System.out.println(fatherName); 

    responseToUser(addEmployee(name,surname,fatherName,department, age),response); 

    } 

public boolean addEmployee(String name, String surname, String fathername, String department, Integer age) { 
    AllWorkers workers = new AllWorkers(); 
    if (!name.equals("") && !surname.equals("") && !fathername.equals("") && !dep artment.equals("") && age != null) { 
     Person person = new Person(surname, name, fathername, department, age); 
     Departments dep = Departments.valueOf(person.getDepartment()); 
     if (dep == Departments.логистика) { 
      workers.addLogistic(person); 
     } else if (dep == Departments.продажи) { 
      workers.addSales(person); 
     } 
     return true; 
    } else { 
     return false; 
    } 
} 

public void responseToUser(boolean boo, HttpServletResponse response) throws IOException { 
    Gson gson = new Gson(); 
    response.setContentType("application/json"); 
    if(boo == true){ 
     response.getWriter().write(gson.toJson(true)); 
    }else if(boo == false){ 
     response.getWriter().write(gson.toJson(false)); 
    } 
} 

部門：

public enum Departments { 
    логистика,продажи 
} 

AllWorkers.java

public class AllWorkers { 

    LinkedList<Person> logistic = new LinkedList<Person>(); 
    LinkedList<Person> sales = new LinkedList<Person>(); 

    public void addLogistic(Person person){ 
     logistic.add(person); 
    } 
    public void addSales(Person person){sales.add(person);} 

    public LinkedList<Person> getLogistic() { 
     return logistic; 
    } 

    public LinkedList<Person> getSales() { 
     return sales; 
    } 
} 

Person.java

public class Person { 
    private String name; 
    private String surname; 
    private String fatherName; 
    private String department; 
    private int age; 

    Person(){ 

    } 

    Person(String name, String surname, String fatherName,String department, int age){ 
     this.name = name; 
     this.surname = surname; 
     this.fatherName = fatherName; 
     this.department = department; 
     this.age = age; 


    } 

    public String getDepartment() { 
     return department; 
    } 

    public String getFatherName() { 
     return fatherName; 
    } 

    public int getAge() { 
     return age; 
    } 

    public String getSurname() { 
     return surname; 
    } 

    public String getName() { 
     return name; 
    } 

    public void setName(String name) { 
     this.name = name; 
    } 

    public void setAge(int age) { 
     this.age = age; 
    } 

    public void setFatherName(String fatherName) { 
     this.fatherName = fatherName; 
    } 

    public void setSurname(String surname) { 
     this.surname = surname; 
    } 

    public void setDepartment(String department) { 
     this.department = department; 
    } 
} 

Answer 1

（我假設你已經檢查了你的變量name，surname，fatherName，department和age有正確的價值觀）

我已經測試你的代碼和個人加入到包含在AllWorkers正確LinkedLists。然而，在方法addEmploye()你這樣做：

AllWorkers workers = new AllWorkers(); 

這意味着你創建你comsume servlet的，每一次workers將是空的，因爲它是一個新的對象一個新workers每次。也許這就是人們似乎沒有被添加到列表中的原因。

Regards，