undergraduate.java

关于JAVA的代码连接数据库

package GradeManagement.model;
import java.io.EOFException;
import GradeManagement.util.SystemConstants;

// 声明Undergraduate类
public class Undergraduate extends Student {
  int grade;      // 论文分数
  String article; // 论文标题

  public Undergraduate(){}

  public Undergraduate(String id, String name,
                  CourseGrade grades[],
                  int grade, String article) {
    super(id, name, grades);
    this.setGrade(grade);
    this.setArticle(article);
  }

  public Undergraduate(Undergraduate graStudent) {
    super(graStudent);
    setGrade(graStudent.getGrade());
    setArticle(graStudent.getArticle());
  }

  /*********属性相应的get/set方法*************/
  public int getGrade() {
    return grade;
  }

  public String getArticle() {
      return this.article;
  }

  public void setGrade(int grade) {
    this.grade = grade;
  }

  public void setArticle(String article) {
    this.article = article;
  }

  public String toString() {
    return super.toString() + getGrade() + "\t" + this.getArticle()+ "\t";
  }

  public int compareTo(Object anObject){
    return compareTo((Undergraduate)anObject);
  }

  //比较成绩大小,当前对象成绩比参数对象成绩大时返回1,相等时返回0,其它返回-1.
  public int compareTo(Undergraduate anObject){
    if( this == anObject) return 1;
     if(this.sum() > anObject.sum()) return 1;
       else if(this.sum() == anObject.sum()) return 0;
         else return -1;
  }

  public float sum() {
    return( super.sum() + grade );//研究生加上论文分数
  }

 public float average() {
    return sum() / (SystemConstants.UNDGRSCOURSES.length + 1);
  }

  //第六章新增代码
  public  boolean readRecord() {
    if (!super.readRecord()) return false; // 调用父类方法readRecord()
    boolean readSucess = true;          // 读入成功标志
    try {
      grade = file.readInt();		// 读入论文分数
      // 读入论文标题
      byte articleByte[] = new byte [MAX_STRING_SIZE];
      file.readFully(articleByte);
      article = new String(articleByte).trim();
    } catch(EOFException eoException) {
      System.out.println("end of file end");
    }
    catch(Exception e){
      readSucess = false;
    };
    return readSucess;
  } // 方法readRecord结束

  public  int getCourseNumbers(){
    return SystemConstants.UNDGRSCOURSES.length;
  }

  //第六章新增代码
  public  boolean writeRecord() {
    if(!super.writeRecord()) return false;
    try {
      file.writeInt(grade);      //写入论文分数
      byte b1[] = process(article);
      file.write(b1);  //写入研究生需要写论文
    } catch(Exception e) {
      return false;
    }
    return true;
  } // 方法writeRecord()结束
} // 类Undergraduate结束