Java读取properties文件并加载到内存

直接上代码：

import java.io.InputStream;

import java.util.Properties;
public class ReadProperties {
    static private String driver = null;
    static private String url = null;
    static private String user = null;
    static private String password = null;
    static{
        loads();
    }
    synchronized static public void loads(){
        if(driver == null || url == null || user == null || password == null){
            InputStream is = ReadProperties.class.getResourceAsStream("/db.properties");
            Properties dbproperties = new Properties();
            try {
                dbproperties.load(is);
                      
                driver = dbproperties.getProperty("driver").toString();
                url = dbproperties.getProperty("url").toString(); 
                user = dbproperties.getProperty("user").toString(); 
                password = dbproperties.getProperty("password").toString();
                  
            }
            catch (Exception e) {
                System.err.println("不能读取属性文件. " + "请确保db.properties在CLASSPATH指定的路径中");
            }
        }
    }
    
    public static String getDriver() {
        if(driver==null)
            loads();
        return driver;
    }
   
    public static String getUrl() {
        if(url==null)
            loads();
        return url;
    }
   
    public static String getUser() {
        if(user==null)
            loads();
        return user;
    }
   
    public static String getPassword() {
        if(password==null)
            loads();
        return password;
    }
 
}

这个方法不仅能够缓存配置文件内容，还能够做到自动加载配置文件的内容到内存，使用者完全不用考虑手动加载的过程，只需要在需要用到的地方直接调用ReadProperties的get方法[例：String url = ReadProperties.getgetUrl()]就可以了（因为是静态方法，不用创建对象），这样如果内存中有缓存，函数就会直接读取内存中的数据，节省时间，如果没有缓存系统也会自动加载