读取properties配置文件

读取properties配置文件

PropertiesUtil.java、template.properties、Main.java处于同一目录

1、PropertiesUtil.javatemplate.properties类

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

/**
 * Created by jaer on 2016/10/10.
 * 读取配置文件类
 */
public class PropertiesUtil {
private static Properties prop;
private static PropertiesUtil instance = new PropertiesUtil();

/** 文件名称 */
private String proFileStr = "template";

public PropertiesUtil() {
//properties文件的路径
        String templatePath = System.getProperty("user.dir") + File.separator + "src\\" + proFileStr + ".properties";
if (prop == null) {
            prop = new Properties();
            File f = new File(templatePath);
            FileInputStream in = null;
try {
                in = new FileInputStream(f);
                prop.load(in);
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
    }

public static synchronized PropertiesUtil getInstance() {
if (prop == null) {
            instance = new PropertiesUtil();
        }
return instance;
    }

public String getProperties(String key, String defaultVal) {
return prop.getProperty(key) == null ? defaultVal : prop.getProperty(key);
    }
}

2、template.properties文件

usname=root
password=123456

3、测试类Main.java文件

public class Main {
public static void main(String[] args) {
        String usname = PropertiesUtil.getInstance().getProperties("usname","zhangsan");
        System.out.println(usname);
    }
}

输出

#如果没有获取到相应的值，使用默认值
root