Java读取properties配置文件的实现过程

package com.proven.util;

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

/**
 * 
* @ClassName: PropertyUtil  
* @author weilong  
* @date 2019年5月14日
 */
public class PropertyUtil {
    private static Properties props;
    static{
        loadProps();
    }

    synchronized static private void loadProps(){
        props = new Properties();
        InputStream inputStream=null;
        try {
        	inputStream = new BufferedInputStream(new FileInputStream(new File("config/config.properties")));
            props.load(inputStream);
        } catch (FileNotFoundException e) {
            System.out.println("config.properties文件未找到");
        } catch (IOException e) {
        	System.out.println("出现IOException");
        } finally {
            try {
                if(null != inputStream) {
                	inputStream.close();
                }
            } catch (IOException e) {
            	System.out.println("config.properties文件流关闭出现异常");
            }
        }
        System.out.println("加载properties文件内容完成...........");
    }

    public static String getProperty(String key){
        if(null == props) {
            loadProps();
        }
        return props.getProperty(key);
    }

    public static String getProperty(String key, String defaultValue) {
        if(null == props) {
            loadProps();
        }
        return props.getProperty(key, defaultValue);
    }
    
    public static void setProperty(String key,String value) {
    	try {
    		if(null == props) {
                loadProps();
            }
			FileOutputStream oFile = new FileOutputStream(new File("config/config.properties"));
			props.setProperty(key, value);
			props.store(oFile, new Date().toString());
			oFile.close();
		} catch (IOException e) {
			
			e.printStackTrace();
		}
	 
	  
    }
}

PropertyUtil.getProperty(key),PropertyUtil.setProperty(key,value)