import java.io.FileNotFoundException;import java.io.IOException;import java.io.InputStream;import java.util.Properties;/** *  1 读取src下的配置文件 * 工具类 */public class Util {    public Util() {    }    public static Properties prop = null;        private static final String FILENAME = "constant.properties";        public static Properties getPara() {        prop = new Properties();        try {            InputStream is = Util.class.getClassLoader().getResourceAsStream(FILENAME);            prop.load(is);        } catch (Exception e) {            e.printStackTrace();        }        return prop;    }        /**     *     * @param key     * @return     */    public static String readproperty(String key) {        if(null == prop){            Util.getPara();        }        try {            prop.load(Util.class.getClassLoader().getResourceAsStream(FILENAME));            return prop.getProperty(key);        } catch (FileNotFoundException e) {        } catch (IOException e) {        }        return null;    }        }