java读取，写入properties文件，Properties工具类

 

一.用ResourceBundle

ResourceBundle rb = ResourceBundle.getBundle("env"); //没有.properties结尾
String driver = rb.getString("jdbc.driverClassName");

 

二.用Properties

Properties env = new Properties();

//InputStream is = 当前类.class.getClassLoader().getResourceAsStream("/env.properties")

InputStream is = 当前类.class.getClassLoader().getResourceAsStream("env.properties")

//InputStream is = ClassLoader.getSystemResourceAsStream("env.properties");
env.load(is);

env.getProperty("jdbc.driverClassName")

第一种要写/，第三种在web容器下会有问题，因为web容器有多个ClassLoader，会找不到文件。

 

env.properties

jdbc.driverClassName= oracle.jdbc.driver.OracleDriver
jdbc.url= jdbc:oracle:thin:@192.168.1.186:1521:orcl
jdbc.username=xxx
jdbc.password=xxx

  

Properties工具类

import java.io.File;
import java.io.FileOutputStream;
import java.io.InputStream;
import java.util.Properties;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;

/**
 * Properties工具类
 * @author happyqing
 * @since 2014.6.6
 */
public class PropertiesUtil {
    private static final Log log = LogFactory.getLog(PropertiesUtil.class); 
    private static Properties env = new Properties();
    
    static {
		try {
	        //PropertiesHelper.class.getResourceAsStream("env.properties"); // /com/cici/conf/env.properties
	        //ClassLoader.getSystemResourceAsStream("env.properties");
	        InputStream is = PropertiesUtil.class.getClassLoader().getResourceAsStream("env.properties");
	        env.load(is);
	        is.close();
		} catch (Exception e) {
	        log.error(e);
		}
    }
    
    /**
     * 取属性值
     * @param key
     * @return 
     */
    public static String getProperty(String key){
        return env.getProperty(key);
    }
    
    /**
     * 设置属性值
     * @param key
     * @param value 
     */
    public static void setProperty(String key, String value){
        try{
            File file = new File(PropertiesUtil.class.getClassLoader().getResource(".").getPath()+File.separator+"env.properties");
            FileOutputStream outStream = new FileOutputStream(file);
            env.setProperty(key, value);
            //写入properties文件
            env.store(outStream, null);
        } catch (Exception ex) {
            log.error(ex);
        }
    }
    
    public static void main(String[] args) {
        // TODO Auto-generated method stub
        System.out.println(PropertiesUtil.getProperty("txtLength"));
        //System.out.println(PropertiesUtil.class.getClassLoader().getResource(".").getPath());
    }
}

 

JAVA操作properties文件

http://www.cnblogs.com/panjun-Donet/archive/2009/07/17/1525597.html

Java读取Properties文件的六种方法

http://hi.baidu.com/hgd0324/item/1d5e923973b77c4d033edcaf