关于hbase的java客户端操作。百度不到。

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关于hbase的java客户端操作。百度不到。0

配置文件,在src下
hbase-site.xml

 <configuration>
 <property>
 <name>hbase.rootdir</name>
 <value>hdfs://sun247:9000/hbase</value>
 </property>
 <property>
 <name>hbase.cluster.distributed</name>
 <value>true</value>
</property>
 <property>
 <name>hbase.zookeeper.quorum</name>
 <value>*.*.*.*, *.*.*.*, *.*.*.*</value>
 </property>
 <property skipInDoc="true">
 <name>hbase.defaults.for.version</name>
 <value>0.94.8</value>
 </property>
 </configuration>

hbase的工具类

	static{
		HBaseConfiguration.create();
	}
public static Result selectRow(String tableName, String rowKey) throws IOException{
		if(StringUtils.isBlank(tableName) || StringUtils.isBlank(rowKey))
			return null;
		Result result = null;
		try {
			HTable table = new HTable(config, tableName);
			Get get = new Get(rowKey.getBytes());
			result = table.get(get);
		} catch (IOException e) {
			log.error("查询错误", e);
			new Throwable("at HbaseUtil.selectRow() error");
		}
		return result;
		
	}

junit测试类

	public void testSelectRow(){
		try {
			Result result = HbaseUtil.selectRow("H_User", "100");
			for(KeyValue keyValue : result.raw()){
				System.out.println(keyValue.getRow());
			}
		} catch (IOException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}
	}

报错

java.lang.NullPointerException
	at org.apache.hadoop.hbase.client.ServerCallable.withRetries(ServerCallable.java:153)
	at org.apache.hadoop.hbase.client.HTable.get(HTable.java:677)
	at cn.duduniu.fj.util.HbaseUtil.selectRow(HbaseUtil.java:51)
	at cn.duduniu.fj.util.TestHbaseUtil.testSelectRow(TestHbaseUtil.java:14)
	at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
	at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
	at java.lang.reflect.Method.invoke(Method.java:616)
	at junit.framework.TestCase.runTest(TestCase.java:168)
	at junit.framework.TestCase.runBare(TestCase.java:134)
	at junit.framework.TestResult$1.protect(TestResult.java:110)
	at junit.framework.TestResult.runProtected(TestResult.java:128)
	at junit.framework.TestResult.run(TestResult.java:113)
	at junit.framework.TestCase.run(TestCase.java:124)
	at junit.framework.TestSuite.runTest(TestSuite.java:243)
	at junit.framework.TestSuite.run(TestSuite.java:238)
	at org.junit.internal.runners.JUnit38ClassRunner.run(JUnit38ClassRunner.java:83)
	at org.eclipse.jdt.internal.junit4.runner.JUnit4TestReference.run(JUnit4TestReference.java:50)
	at org.eclipse.jdt.internal.junit.runner.TestExecution.run(TestExecution.java:38)
	at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:467)
	at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:683)
	at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.run(RemoteTestRunner.java:390)
	at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.main(RemoteTestRunner.java:197)

第一次操作，代码参考网络的。但是报错了。百度不到。

HBase