Hbase QualifierFilter用于过滤qualifier,也就是一个列族里面data:xxx,冒号后面的字符串。 =。= package com.fatkun.filter.comparison;import java.io.IOException;import org.apache.hadoop.conf.Configuration;import org.apache.hadoop.hbase.HBaseCon
Hbase QualifierFilter用于过滤qualifier,也就是一个列族里面data:xxx,冒号后面的字符串。 =。=
package com.fatkun.filter.comparison; import java.io.IOException; import org.apache.hadoop.conf.Configuration; import org.apache.hadoop.hbase.HBaseConfiguration; import org.apache.hadoop.hbase.HColumnDescriptor; import org.apache.hadoop.hbase.HTableDescriptor; import org.apache.hadoop.hbase.client.Get; import org.apache.hadoop.hbase.client.HBaseAdmin; import org.apache.hadoop.hbase.client.HTable; import org.apache.hadoop.hbase.client.Put; import org.apache.hadoop.hbase.client.Result; import org.apache.hadoop.hbase.client.ResultScanner; import org.apache.hadoop.hbase.client.Scan; import org.apache.hadoop.hbase.filter.BinaryComparator; import org.apache.hadoop.hbase.filter.CompareFilter; import org.apache.hadoop.hbase.filter.FamilyFilter; import org.apache.hadoop.hbase.filter.Filter; import org.apache.hadoop.hbase.filter.QualifierFilter; import org.apache.hadoop.hbase.util.Bytes; public class TestHbaseQualifierFilter { String tableName = "test_qualifier_filter"; Configuration config = HBaseConfiguration.create(); /** * 部分代码来自hbase权威指南 * @throws IOException */ public void testRowFilter() throws IOException { HTable table = new HTable(config, tableName); Scan scan = new Scan(); System.out.println("只列出小于col5的列"); Filter filter1 = new QualifierFilter(CompareFilter.CompareOp.LESS, new BinaryComparator(Bytes.toBytes("col5"))); scan.setFilter(filter1); ResultScanner scanner1 = table.getScanner(scan); for (Result res : scanner1) { System.out.println(res); } scanner1.close(); System.out.println("get也可以设置filter"); Get get1 = new Get(Bytes.toBytes("row003")); get1.setFilter(filter1); Result result1 = table.get(get1); System.out.println("Result of get(): " + result1); } /** * 初始化数据 */ public void init() { // 创建表和初始化数据 try { HBaseAdmin admin = new HBaseAdmin(config); if (!admin.tableExists(tableName)) { HTableDescriptor htd = new HTableDescriptor(tableName); HColumnDescriptor hcd1 = new HColumnDescriptor("data1"); htd.addFamily(hcd1); HColumnDescriptor hcd2 = new HColumnDescriptor("data2"); htd.addFamily(hcd2); HColumnDescriptor hcd3 = new HColumnDescriptor("data3"); htd.addFamily(hcd3); admin.createTable(htd); } HTable table = new HTable(config, tableName); table.setAutoFlush(false); int count = 50; for (int i = 1; i <p class="copyright"> 原文地址:Hbase QualifierFilter, 感谢原作者分享。 </p>

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Betul -betul

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