Java读取properties文件

Java读取properties文件

Java对properties配置文件的操作

/*
 * Created on 2005-1-4
 *
 * TODO To change the template for this generated file go to
 * Window - Preferences - Java - Code Style - Code Templates
 */
package com.yorsun;

import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.util.Properties;

import javax.servlet.ServletContext;
import javax.servlet.http.HttpServlet;

/**
 * @author Administrator
 *
 * TODO To change the template for this generated type comment go to Window -
 * Preferences - Java - Code Style - Code Templates
 */
public class PropertiesUnit {
 private String filename;

 private Properties p;

 private FileInputStream in;

 private FileOutputStream out;

 public PropertiesUnit(String filename) {
  this.filename = filename;
  File file = new File(filename);
  try {
   in = new FileInputStream(file);
   p = new Properties();
   p.load(in);
   in.close();
  } catch (FileNotFoundException e) {
   // TODO Auto-generated catch block
   System.err.println("配置文件config.properties找不到！");
   e.printStackTrace();
  } catch (IOException e) {
   // TODO Auto-generated catch block
   System.err.println("读取配置文件config.properties错误！");
   e.printStackTrace();
  }
 }

 public static String getConfigFile(HttpServlet hs) {
  return getConfigFile(hs, "config.properties");
 }

 /**
  * @param hs
  * @param configFileName
  * @return configFile
  */
 private static String getConfigFile(HttpServlet hs, String configFileName) {
  String configFile = "";
  ServletContext sc = hs.getServletContext();
  configFile = sc.getRealPath("/" + configFileName);
  if (configFile == null || configFile.equals("")) {
   configFile = "/" + configFileName;
  }
  // TODO Auto-generated method stub
  return configFile;
 }

 public void list() {
  p.list(System.out);
 }

 public String getValue(String itemName) {
  return p.getProperty(itemName);
 }

 public String getValue(String itemName, String defaultValue) {
  return p.getProperty(itemName, defaultValue);
 }

 public void setValue(String itemName, String value) {
  p.setProperty(itemName, value);
 }

 public void saveFile(String filename, String description) throws Exception {
  try {
   File f = new File(filename);
   out = new FileOutputStream(f);
   p.store(out, description);
   out.close();
  } catch (IOException ex) {
   throw new Exception("无法保存指定的配置文件:" + filename);
  }
 }
 
 public void saveFile(String filename) throws Exception{
  saveFile(filename,"");
 }
 
 public void saveFile() throws Exception{
  if(filename.length()==0)
   throw new Exception("需指定保存的配置文件名");
  saveFile(filename);
 }
 
 public void deleteValue(String value){
  p.remove(value);
 }
 
 public static void main(String args[]){
  String file="/eclipse/workspace/NewsTest/WEB-INF/config.properties";
//  String file="D:\\eclipse\\workspace\\NewsTest\\WEB-INF\\config.properties";
  PropertiesUnit pu=new PropertiesUnit(file);
  pu.list();
 }

}