Hadoop配置属性返回Null

该资源需要添加为URL,否则String将被解释为类路径资源(目前无法解析并被忽略-我知道你认为警告消息会被转储到某个地方):

/**
 * Add a configuration resource. 
 * 
 * The properties of this resource will override properties of previously 
 * added resources, unless they were marked <a href="#Final">final</a>. 
 * 
 * @param name resource to be added, the classpath is examined for a file 
 *             with that name.
 */
public void addResource(String name) {
  addResourceObject(name);
}

无论如何,试试这个(我在系统错误中得到黄色):

@Test
public void testConf() throws MalformedURLException {
    Configuration conf = new Configuration();

    conf.addResource(new File("~/conf.xml")
            .getAbsoluteFile().toURI().toURL());
    conf.reloadConfiguration();
    System.err.println(conf);

    System.err.println(conf.get("color"));
}