获取Properties类

import java.io.BufferedInputStream;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.util.Enumeration;
import java.util.Properties;

/**
 * @author SiPei.Qiao
 * @function 获取Properties类
 */
public class GetProperties {
	
	private static PathUtil f = new PathUtil();
	private static String path = f.getWebClassesPath()+"Configs/ftp/ftpInfo.properties";
	
	//根据key读取value
	public static String readValue(String filePath,String key) 
	{
		  Properties props = new Properties();
		        try {
		         InputStream in = new BufferedInputStream (new FileInputStream(filePath));
		         props.load(in);
		         String value = props.getProperty (key);
		            //输出部分为调试使用
		            System.out.println(key+"|"+value);
		            return value;
		        } catch (Exception e) {
		         e.printStackTrace();
		         return null;
		        }
     }
	//读取properties的全部信息
	 public static void readProperties(String filePath) 
	 {
	     Properties props = new Properties();
	        try {
	         InputStream in = new BufferedInputStream (new FileInputStream(filePath));
	         props.load(in);
	            Enumeration en = props.propertyNames();
	             while (en.hasMoreElements()) {
	              String key = (String) en.nextElement();
	                    String Property = props.getProperty (key);
	                    //输出部分为调试使用
	                    System.out.println(key+"|"+Property);
	                }
	        } catch (Exception e) {
	         e.printStackTrace();
	        }
	    }
	 
      public static void writeProperties(String filePath,String parameterName,String parameterValue) 
      {
        Properties prop = new Properties();
        try {
         InputStream fis = new FileInputStream(filePath);
               //从输入流中读取属性列表（键和元素对）
               prop.load(fis);
               //调用 Hashtable 的方法 put。使用 getProperty 方法提供并行性。
               //强制要求为属性的键和值使用字符串。返回值是 Hashtable 调用 put 的结果。
               OutputStream fos = new FileOutputStream(filePath);
               prop.setProperty(parameterName, parameterValue);
               //以适合使用 load 方法加载到 Properties 表中的格式，
               //将此 Properties 表中的属性列表（键和元素对）写入输出流
               prop.store(fos, "Update '" + parameterName + "' value");
           } catch (IOException e) {
            System.err.println("Visit "+filePath+" for updating "+parameterName+" value error");
           }
       }
      //构造main方法用于调试各方法使用
      public static void main(String[] args) 
      {
    	        readValue(path,"UpLoadPath");
    	        //writeProperties(path,"UpLoadPath","Files_Up");
    	        readProperties(path);
    	        System.out.println("OK");
      }
	
}