studentcmpclient.java

java的一系列产品中包括jsme,jmse,j2ee,本文件提供j2ee实现的源代码.

package cmp;

import java.rmi.RemoteException;
import java.util.ArrayList;
import java.util.Collection;
import java.util.Iterator;
import java.util.List;
import java.util.Properties;

import javax.ejb.CreateException;
import javax.naming.Context;
import javax.naming.InitialContext;
import javax.naming.NamingException;
import javax.rmi.PortableRemoteObject;

public final class StudentCMPClient extends BaseClient {
  private StudentHome studentHome;
  private BookHome bookHome;
  private TeacherHome teacherHome;
  private FamilyHome familyHome;

 private Context ctx;

  public StudentCMPClient(String [] argv) throws NamingException{
    super(argv);
    ctx = getInitialContext();
    studentHome = 
      (StudentHome) narrow(ctx.lookup("StudentCMPEJB"), StudentHome.class);

    bookHome = (BookHome) narrow(ctx.lookup("BookCMPEJB"), BookHome.class);
    teacherHome = 
      (TeacherHome)narrow(ctx.lookup("TeacherCMPEJB"), TeacherHome.class);
    
    familyHome = (FamilyHome)narrow(ctx.lookup("FamilyCMPEJB"),
       FamilyHome.class);
  }
  
  public static void main(String[] argv) throws Exception
  {
    StudentCMPClient sc = new StudentCMPClient(argv);
    sc.runClient();
  }
  
  private void runClient() throws Exception{
    System.out.println("Running CMP Mmnager Relation Example.\n");
    Student [] students = null;
    Family  [] familys  = null;
    Book    [] books    = null;
    Teacher [] teachers = null;
    try {
      students = createStudents();    
      // create 1 family for each student
      familys  = createFamilys(students.length);      
      // create 1 book for each student;
      books = createBooks(students.length);      
      teachers = createTeachers();
    } catch (Exception e) {
      System.err.println("Unable to create the CMP Example.");           
    }
    System.out.println("Updating relationships....\n");
    
    // Assign each Student a Family
    System.err.println("Assigning each Student to a Family.");
    for (int i=0; i<students.length; i++) {
      students[i].assignFamily(familys[i]);
    }

    // Assign the books out to the students
    System.err.println("Assigning books to each Student.");
    for (int i=0; i<books.length; i++) {      
      students[i % students.length].assignBook(books[i]);
    }
    
    // Assign students to teachers
    // Student 0 gets teacher 0
    // Student 1 gets teacher 0,1 etc.
    System.err.println("Assigning Students to Teachers.\n");
    for (int i=0; i<teachers.length; i++) {      
      for (int j=0; j<i; j++) {
        students[j].assignTeacher(teachers[i]);
      }
    }

    System.out.println("Finding All the Students in grade 5:");    
    try {
      Collection c = studentHome.findStudentsInGrade(5);
      if (c.isEmpty()) {
        System.err.println("No Students were found in grade 5.");
      } else {
        Iterator it = c.iterator();
        while (it.hasNext()) {
          Student s = (Student) narrow(it.next(), Student.class);
          System.err.println("Found student named: "+s.getName()+
            " in grade 5.");
        }
        System.out.println("");
      }
    } catch (Exception e) {
      System.err.println("Unable to find students in grade 5.");
      System.err.println("The error was: ");
      //e.printStackTrace();
      //throw e;
    }
    
    System.out.println("Finding the Students with a Family:");    
    try {
      Collection c = studentHome.findStudentsWithAFamily(2);
      if (c.isEmpty()) {
        System.out.println("No Students were found with Familys.");
      } else {
        Iterator it = c.iterator();
        while (it.hasNext()) {
          Student s = (Student) narrow(it.next(), Student.class);
          System.err.println("Found student named: "+s.getName()+
            " with a Family");
        }
        System.out.println("");
      }
    } catch (Exception e) {
      System.err.println("Unable to find students with Familys.\n");
      System.err.println("The error was: ");
   }

   System.out.println("Finding All the Students with a Book:");
   
   try {
      Collection c = studentHome.findStudentsWithBooksTitled("C/C++ program");
      if (c.isEmpty()) {
        System.err.println("No Students were found with books named Hamlet.");
      } else {
        Iterator it = c.iterator();
        while (it.hasNext()) {
          Student s = (Student) narrow(it.next(), Student.class);
          System.err.println("Found student named: "+s.getName()+
            " with a book named C/C++ program.");
        }
        System.err.println("");
      }
    } catch (Exception e) {
      System.err.println("Unable to find students WITH books named Hamlet.");
      System.err.println("The error was: ");
    }
  }
      
  //Create Beans For CMP Examples
  private Student[] createStudents() throws CreateException,RemoteException
  {
    System.out.println("Creating Student CMP Beans...");
    String [] names ={"LiMing","WangHong","YangYang","Mike","Peter" };
    deleteOldStudents(names.length);
    Student [] students = new Student[names.length];
    for (int i=0; i<names.length; i++) {      
      //create 5 students in grade 2 or 5
      if(i%2!=0) //奇数学生的班级设为2
      	students[i] = studentHome.create(names[i], i, 2);
       else
        students[i] = studentHome.create(names[i], i, 5);
    }
    return students;
  }

  private Family[] createFamilys(int N) throws CreateException,RemoteException
  {
    System.out.println("Creating Family CMP Beans...");
    deleteOldFamilys(N);
    Family [] familys = new Family[N];
    for (int i=0; i<N; i++){      
      //reate students in 5 family
      familys[i] = familyHome.create(new Integer(i),"YangGao Road No "+i);
    }
    return familys;
  }

  private Teacher [] createTeachers() 
    throws CreateException, RemoteException
  {
    System.err.println("Creating Teacher CMP Beans...");
    String [] names = { "Jack", "Jim", "HaLi Han", "TinXianShen"};
    deleteOldTeachers(names.length);
    Teacher [] teachers = new Teacher[names.length];
    for (int i=0; i<names.length; i++){      
      // create our teachers
      teachers[i] = teacherHome.create(names[i], new Integer(i));
    }
    return teachers;
  }

  private Book[] createBooks(int numCopies) throws CreateException,RemoteException
  {
    System.out.println("Creating Book CMP beans...");

    String [] titles = {"C/C++ program", "Java Think", "Data Structure"};
    String [] authors = {"ZhanJunGu", "ZhangHZ", "SuHong"};

    deleteOldBooks(titles.length, numCopies);
    Book [] books = new Book[titles.length * numCopies];
    for (int i=0; i<titles.length; i++) {      
      for (int j=0; j<numCopies; j++) {
        books[i*numCopies+j] = 
          bookHome.create(authors[i],titles[i],String.valueOf(i),j);
      }
    }
    return books;
  }
  // Utility code
  private void deleteOldFamilys(int N) {    
    for (int i=0; i<N; i++) {
      try {
        familyHome.remove(new Integer(i));
      } catch (Exception ignore) {}
    }
  }

  private void deleteOldStudents(int N) {    
    for (int i=0; i<N; i++) {
      try {
        studentHome.remove(new Integer(i));
      } catch (Exception ignore) {}
    }
  }

  private void deleteOldTeachers(int N) {    
    for (int i=0; i<N; i++) {
      try {
        teacherHome.remove(new Integer(i));
      } catch (Exception ignore) {}
    }
  }

  private void deleteOldBooks(int N, int numCopies) {    
    BookPK pk;
    for (int i=0; i<N; i++) {      
      for (int j=0; j<numCopies; j++) {
        try {
          pk = new BookPK(String.valueOf(i), j); 
          bookHome.remove(pk);
        } catch (Exception ignore) {}
      }
    }
  }
}