fileutility.java

抽奖系统。营销活动现场

//FileUtitlty.java
package com.cy;

import java.io.*;
import java.util.*;

public class FileUtility {
  static final String MAGIC_STRING = "WONDER";
  static Vector v1 = null;
  static Vector v2 = null;

  /**
   * 从数据文件装入数据
   */
  static void loadData(String name) throws Exception{
    v1 = null;
    v2 = null;
    FileInputStream in ;
    in = new FileInputStream(name);
    ObjectInputStream s = new ObjectInputStream(in);
    String magic = (String)s.readObject();
    v1 = (Vector)s.readObject();
    v2 = (Vector)s.readObject();
    s.close();
    in.close();
  }

  /**
   * 将数据保存到文件
   */
  static void saveData(String name,Vector v1, Vector v2) throws Exception{
    FileOutputStream out = new FileOutputStream(name);
    ObjectOutputStream s  = new ObjectOutputStream(out);
    s.writeObject(MAGIC_STRING);
    s.writeObject(v1);
    s.writeObject(v2);
    s.close();
    out.close();
  }

  /**
   * 输出csv文件
   */
  static void outputCSVFile(String fileName,String[] columnName,Vector data) throws Exception{
    FileWriter fw = new FileWriter(fileName);
    PrintWriter out = new PrintWriter(fw);
    for (int i=0;i<columnName.length -1;i++){
      out.print(columnName[i]);
      out.print(",");
    }
    out.println(columnName[columnName.length-1]);

    for (int i=0;i<data.size();i++){
      UserInfo info=(UserInfo)data.elementAt(i);
      String[] array = info.getUserInfoArray();
      for (int j=0;j<array.length-1;j++){
        out.print(array[j]);
        out.print(",");
      }
      out.println((String)array[array.length-1]);
    }
    out.close();
    fw.close();
  }


  /**
   * 看文件是否存在
   */
  public static boolean exist(String name){
    File f= new File(name);
    return f.exists();
  }

  /**
   * 验证是否是合法的数据文件
   */
  public static boolean isFileValid(String name){
    if (exist(name)==false){
      return false;
    }
    try {
      FileInputStream in = new FileInputStream(name);
      ObjectInputStream s = new ObjectInputStream(in);
      String head = (String)s.readObject();
      if (head.equals(MAGIC_STRING)){
        return true;
      }
      else{
        return false;
      }
    }
    catch (Exception ex) {
      ex.printStackTrace();
      return false;
    }
  }

  /**
   * 获得当前文件的后缀名
   */
  public static String getSuffix(File f){
    String s = f.getPath();
    return getSuffix(s);
  }

  /**
   * 获得当前文件的后缀名
   */
  public static String getSuffix(String name){
    String s = name;
    String suffix = null;
    int i = s.lastIndexOf('.');
    if (i>0&&i<s.length()-1){
      suffix = s.substring(i+1).toLowerCase();
    }
    return suffix;
  }

  /**
   * 建立测试数据文件
   */
  public static void createTextFile(){
    Vector v = new Vector();
    Vector v1= new Vector();
    UserInfo info;
    for ( int i=0 ; i<100; i ++){
      info = new UserInfo();
      info.setSn(i);
      info.setAge(20+i%40);
      info.setName("User"+i);
      info.setPhone("8888-8888");
      info.setIdCard("1245678980");
      v.addElement(info);
    }
    try {
       saveData("testdata.dat",v,v1);
    }
    catch (Exception ex) {
      ex.printStackTrace();
    }
  }

  public static void main(String argv[]){
    createTextFile();
  }

}