2014-03-07 369 views
0

解決此問題有一些麻煩。我一直在使用我之前完成的一個例子來進行協助,它幾乎完全相同並且可行。 addStudents方法中的構造函數不適合,我不確定我做錯了什麼。儘可能多地包含HibernateStudent文件和Student java文件。任何幫助將不勝感激,謝謝。構造函數問題,找不到合適的構造函數

public HibernateStudent3() { 
     Configuration configuration = h2Config(new Class[]{Student.class, Programme.class, Module.class}); 
     sessionFactory = configuration.buildSessionFactory(); 
    } 

    @SuppressWarnings({"unchecked"}) 

    public void addStudents() { 

     System.out.println("Add Students"); 

     Session session = sessionFactory.openSession(); 
     session.beginTransaction(); 
     System.out.println("\n***Session started..."); 

     System.out.println("\n***Creating student objects..."); 
     Student s1 = new Student("1", "Bob", "Dylan", "[email protected]", "ISD"); 
     Student s2 = new Student("2", "Joni", "Mitchell", "[email protected]", "ISD"); 
     Student s3 = new Student("3", "Paul", "Simon", "[email protected]", "ISD");  
     System.out.println("\n***Student objects created..."); 


     System.out.println("\n***Saving student objects..."); 
     session.save(s1); 
     session.save(s2); 
     session.save(s3);   
     System.out.println("\n***Student objects saved..."); 

     session.getTransaction().commit(); 
     session.flush(); 
     session.close(); 
     System.out.println("\n***Session closed..."); 

    } 

    public void listStudents() { 
     System.out.println("List Students"); 

     Session session = sessionFactory.openSession(); 
     session.beginTransaction();   
     System.out.println("\n***Session started...");  

     List studentList = session.createQuery("from Student").list(); 
     System.out.println(studentList.size() + " student(s) found:"); 
     for (Iterator iter = studentList.iterator(); iter.hasNext();) { 
      Student s = (Student) iter.next(); 
      System.out.println(s); 
     } 
     session.getTransaction().commit(); 
     session.flush(); 
     session.close(); 
     System.out.println("\n***Session closed...");   
    } 

    public void addProgrammes() { 

     System.out.println("Add Programmes"); 

     Session session = sessionFactory.openSession(); 
     session.beginTransaction(); 
     System.out.println("\n***Session started..."); 

     System.out.println("\n***Creating programme objects..."); 
     Programme p1 = new Programme("P01627", "Information Systems Development", "FT", null); 
     Programme p2 = new Programme("P00280", "IT Management for Business", "FT", null); 

     System.out.println("\n***Programme objects created..."); 

     System.out.println("\n***Module objects retrieved"); 

     Module m1 = (Module) session.createQuery("from Module where moduleCode = 'M1'").uniqueResult(); 
     Module m2 = (Module) session.createQuery("from Module where moduleCode = 'M2'").uniqueResult(); 
     Module m3 = (Module) session.createQuery("from Module where moduleCode = 'M3'").uniqueResult(); 
     Module m4 = (Module) session.createQuery("from Module where moduleCode = 'M4'").uniqueResult(); 
     Module m5 = (Module) session.createQuery("from Module where moduleCode = 'M5'").uniqueResult(); 
     Module m6 = (Module) session.createQuery("from Module where moduleCode = 'M6'").uniqueResult(); 
     Module m7 = (Module) session.createQuery("from Module where moduleCode = 'M7'").uniqueResult(); 

     Set<Module> p1Modules = new HashSet(Arrays.asList(m1, m2, m3, m4, m5, m6)); 
     Set<Module> p2Modules = new HashSet(Arrays.asList(m1, m2, m3, m4, m5, m7)); 

     System.out.println("\n***Attach modules to programmes"); 

     p1.setModules(p1Modules); 
     p2.setModules(p2Modules); 

     System.out.println("\n***Saving programme objects..."); 
     session.save(p1); 
     session.save(p2);   

     System.out.println("\n***Programme objects saved..."); 

     session.getTransaction().commit(); 
     session.flush(); 
     session.close(); 
     System.out.println("\n***Session closed...");   
    } 

    public void listProgrammes() { 
     System.out.println("List Programmes"); 

     Session session = sessionFactory.openSession(); 
     session.beginTransaction();   
     System.out.println("\n***Session started...");  

     List programmeList = session.createQuery("from Programme").list(); 
     System.out.println(programmeList.size() + " programme(s) found:"); 
     for (Iterator iter = programmeList.iterator(); iter.hasNext();) { 
      Programme p = (Programme) iter.next(); 
      System.out.println(p); 
     } 
     session.getTransaction().commit(); 
     session.flush(); 
     session.close(); 
     System.out.println("\n***Session closed...");   
    }  

    public void addModules() { 

     System.out.println("Add Modules"); 

     Session session = sessionFactory.openSession(); 
     session.beginTransaction(); 
     System.out.println("\n***Session started..."); 

     System.out.println("\n***Creating module objects..."); 
     Module m1 = new Module("M1", "IT Project Management 2"); 
     Module m2 = new Module("M2", "Database Systems Development 2"); 
     Module m3 = new Module("M3", "Research Methods"); 
     Module m4 = new Module("M4", "Professional Issues"); 
     Module m5 = new Module("M5", "Honours Project"); 
     Module m6 = new Module("M6", "Web Programming 2"); 
     Module m7 = new Module("M7", "International Business Strategy");   

     System.out.println("\n***Module objects created..."); 

     System.out.println("\n***Saving module objects..."); 

     session.save(m1); 
     session.save(m2);   
     session.save(m3); 
     session.save(m4); 
     session.save(m5); 
     session.save(m6); 
     session.save(m7);   

     System.out.println("\n***Module objects saved..."); 

     session.getTransaction().commit(); 
     session.flush(); 
     session.close(); 
     System.out.println("\n***Session closed...");   
    } 

    public void listModules() { 
     System.out.println("List Modules"); 

     Session session = sessionFactory.openSession(); 
     session.beginTransaction();   
     System.out.println("\n***Session started...");  

     List moduleList = session.createQuery("from Module").list(); 
     System.out.println(moduleList.size() + " module (s) found:"); 
     for (Iterator iter = moduleList.iterator(); iter.hasNext();) { 
      Module m = (Module) iter.next(); 
      System.out.println(m); 
     } 
     session.getTransaction().commit(); 
     session.flush(); 
     session.close(); 
     System.out.println("\n***Session closed...");   
    }  


    public void studentAdmin() { 

     // Add Modules 
     addModules(); 

     // List Modules 
     listModules();  

     // Add Programmes 
     addProgrammes();   

     // List Programmes 
     listProgrammes();   

     // Add Students 
     addStudents(); 

     // List Students 
     //listStudents();   
    } 

學生類。

public class Student{ 

    private long studentId; 
    private String matricNo; 
    private String firstName; 
    private String surname; 
    private String email; 
    private Programme programme; 

    public Student() { 
     this.matricNo = null; 
     this.firstName = null; 
     this.surname = null; 
     this.email = null; 
     this.programme = null; 
    } 

    public Student(String matric, String fn, String ln) { 
     this.matricNo = matric; 
     this.firstName = fn; 
     this.surname = ln; 
     this.email = null; 
     this.programme = null; 
    } 

    public Student (String matric, String fn, String ln, String e, Programme prg) {   
     this.matricNo = matric; 
     this.firstName = fn; 
     this.surname = ln; 
     this.email = e; 
     this.programme = prg; 
    } 


    public long getStudentId() { 
     return this.studentId; 
    } 

    public void setStudentId(long sid) { 
     this.studentId = sid; 
    } 

    public String getMatricNo() { 
     return this.matricNo; 
    } 

    public void setMatricNo(String matric) { 
     this.matricNo = matric; 
    } 

    public String getFirstName() { 
     return this.firstName; 
    } 

    public void setFirstName(String fn) { 
     this.firstName = fn; 
    } 

    public String getSurname() { 
     return this.surname; 
    } 

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

    public String getEmail() { 
     return this.email; 
    } 

    public void setEmail(String email) { 
     this.email = email; 
    } 

    public Programme getProgramme() { 
     return this.programme; 
    } 

    public void setProgramme(Programme prog) { 
     this.programme = prog; 
    } 

    @Override 
    public int hashCode() { 
     return getMatricNo().hashCode() * 31 + getSurname().hashCode() * 31 + getFirstName().hashCode() * 31 + getEmail().hashCode() * 31 + getProgramme().hashCode(); 
    } 

    @Override 
    public boolean equals(Object o) { 
     if (o instanceof Student) { 
      Student s = (Student)o; 
      return s.getMatricNo() == getMatricNo() && 
        s.getFirstName().equals(getFirstName()) && 
        s.getSurname().equals(getSurname()) && 
        s.getEmail().equals(getEmail()) && 
        s.getProgramme().equals(getProgramme()); 
     } else { 
      return false; 
     } 
    } 

    @Override 
    public String toString() { 
     return "student id: " + getStudentId() + ", " + 
       "matric number: " + getMatricNo() + ", " + 
       "first name: " + getFirstName() + ", " + 
       "surname: " + getSurname() + ", " + 
       "email: " + getEmail() + ", " + 
       "programme: " + getProgramme(); 
    } 
+0

你得到什麼錯誤,在哪裏? –

回答

2

問題:您正在調用Student構造函數,傳入5個字符串。即:

new Student("1", "Bob", "Dylan", "[email protected]", "ISD"); 

但是如果檢查學生類,你會發現它其實沒有這種構造函數,而是一個構造函數的字符串3,另一種需要4個字符串和程序對象(不管這是什麼),所以編譯器是正確的抱怨。

解決方案:您可以爲Student類提供一個有用的5字符串構造函數(但前提是這對您的程序有意義,您需要決定),或者調用其中一個可用的構造函數,例如作爲需要的一個四個字符串和程序引用。

+1

這究竟是如何下降的?常見的瘋狂downvoter,爲自己找到一些和平。 –

+0

@RohitJain:謝謝。 –

+0

至少他們應該提供更好的解決方案。 –

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