Hive源码分析(二) Eclipse调试Hive源码报does not have a scheme错误解决

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     终于可以调试Hive源码了.首当其冲的就报了这个错误:

FAILED: Error in metadata: java.lang.IllegalArgumentException: URI:  does not have a scheme
2011-09-22 11:54:57,890 ERROR [main] session.SessionState$LogHelper(343): FAILED: Error in metadata: java.lang.IllegalArgumentException: URI:  does not have a scheme
org.apache.hadoop.hive.ql.metadata.HiveException: java.lang.IllegalArgumentException: URI:  does not have a scheme
	at org.apache.hadoop.hive.ql.metadata.Hive.getDatabase(Hive.java:1028)
	at org.apache.hadoop.hive.ql.metadata.Hive.databaseExists(Hive.java:1013)
	at org.apache.hadoop.hive.ql.exec.DDLTask.showTables(DDLTask.java:1691)
	at org.apache.hadoop.hive.ql.exec.DDLTask.execute(DDLTask.java:289)
	at org.apache.hadoop.hive.ql.exec.Task.executeTask(Task.java:130)
	at org.apache.hadoop.hive.ql.exec.TaskRunner.runSequential(TaskRunner.java:57)
	at org.apache.hadoop.hive.ql.Driver.launchTask(Driver.java:1063)
	at org.apache.hadoop.hive.ql.Driver.execute(Driver.java:900)
	at org.apache.hadoop.hive.ql.Driver.run(Driver.java:748)
	at org.apache.hadoop.hive.cli.CliDriver.processCmd(CliDriver.java:164)
	at org.apache.hadoop.hive.cli.CliDriver.processLine(CliDriver.java:241)
	at org.apache.hadoop.hive.cli.CliDriver.main(CliDriver.java:456)
Caused by: java.lang.IllegalArgumentException: URI:  does not have a scheme
	at org.apache.hadoop.hive.metastore.HiveMetaStoreClient.<init>(HiveMetaStoreClient.java:127)
	at org.apache.hadoop.hive.ql.metadata.Hive.createMetaStoreClient(Hive.java:1855)
	at org.apache.hadoop.hive.ql.metadata.Hive.getMSC(Hive.java:1865)
	at org.apache.hadoop.hive.ql.metadata.Hive.getDatabase(Hive.java:1024)
	... 11 more

  然后启动后在控制台也收到这样一条Log:hive-log4j.properties not found

 

    源码调下来,发现是Hive在加载配置文件如hive-default.xml,hive-log4j.properties时采用这种方法:

 private ClassLoader classLoader;
  {
    classLoader = Thread.currentThread().getContextClassLoader();
    if (classLoader == null) {
      classLoader = Configuration.class.getClassLoader();
    }
  }

   然后获取hive-default.xml等是采用如下代码:

URL hconfurl = getClassLoader().getResource("hive-default.xml");

   这样在jar中运行是没有问题的,但放到Eclipse里运行的话,获取的路径就会有出路了.现在来验证下:

 

package com.guoyun.hive.study.basic;

public class PrintSourcePath {

	/**
	 * @param args
	 */
	public static void main(String[] args) {
		ClassLoader loader=Thread.currentThread().getContextClassLoader();
		System.out.println("Run path:"+loader.getResource("").getPath());
		// hive-default.xml
		System.out.println("hive-default.xml path:"+loader.getResource("hive-default.xml").getPath());

	}

}

    控制台输出如下：

    Run path:/home/hadoop/workspace/hive-0.7.0/bin/
    Exception in thread "main" java.lang.NullPointerException
    at com.guoyun.hive.study.basic.PrintSourcePath.main(PrintSourcePath.java:12)

   在获取hive-default.xml文件源时报来空指针异常,现在将hive_home/conf下到文件拷到hive/bin下，再运行这个类就不会报错了，我的运行结果如下:

    Run path:/home/hadoop/workspace/hive-0.7.0/bin/

    hive-default.xml path:/home/hadoop/workspace/hive-0.7.0/bin/hive-default.xml

 

  之后再来调试Hive源码，Log:hive-log4j.properties not found已经不出现了。同时也没这个错误来。该问题解决！但接下来又发生了其他错误。。。一步步解决吧。

 

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