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hbase快速入门-- java api 操作

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public class HBase {
public static void main(String[] args) throws IOException {
Configuration conf = new Configuration();
// conf.addResource("hbase-site-cluster.xml");//指定文件加载
conf = HBaseConfiguration.create(conf);
HBaseAdmin admin = new HBaseAdmin(conf);//HBaseAdmin负责跟表相关的操作如create,drop等 

/**========创建表=========*/
HTableDescriptor desc = new HTableDescriptor("blog");
desc.addFamily(new HColumnDescriptor("article"));
desc.addFamily(new HColumnDescriptor("author"));
admin.createTable(desc );
HTable table = new HTable(conf, Bytes.toBytes("blog"));//HTabel负责跟记录相关的操作如增删改查等

/**=========插入数据=========*/

Put put = new Put(Bytes.toBytes("1"));
put.add(Bytes.toBytes("article"), Bytes.toBytes("title"), Bytes.toBytes("Head First HBase"));
put.add(Bytes.toBytes("article"), Bytes.toBytes("content"), Bytes.toBytes("HBase is the Hadoop database. Use it when you need random, realtime read/write access to your Big Data."));
put.add(Bytes.toBytes("article"), Bytes.toBytes("tags"), Bytes.toBytes("Hadoop,HBase,NoSQL"));
put.add(Bytes.toBytes("author"), Bytes.toBytes("name"), Bytes.toBytes("hujinjun"));
put.add(Bytes.toBytes("author"), Bytes.toBytes("nickname"), Bytes.toBytes("一叶渡江"));
table.put(put);
/**=========根据rowkey
Get get = new Get(Bytes.toBytes("1")); 查询数据=========*/
Result result = table.get(get);
  for(KeyValue kv :result.list()){
  System.out.println("family:" +Bytes.toString(kv.getFamily()));
  System.out.println("qualifier:" +Bytes.toString(kv.getQualifier()));
  System.out.println("value:" +Bytes.toString(kv.getValue()));
  System.out.println("Timestamp:" +kv.getTimestamp());
}
/**=========遍历查询=========*/
Scan scan = new Scan();
ResultScanner rs =null;
try {
  rs = table.getScanner(scan);
  for (Result r : rs) {
    for(KeyValue kv :r.list()){
      System.out.println("family:" +Bytes.toString(kv.getFamily()));
      System.out.println("qualifier:" +Bytes.toString(kv.getQualifier()));
      System.out.println("value:" +Bytes.toString(kv.getValue()));
    }
  }
} finally {
  rs.close();
}
/**=========更新=========*/
//查询更新前的值
Get get2 = new Get(Bytes.toBytes("1"));
get2.addColumn(Bytes.toBytes("author"), Bytes.toBytes("nickname"));
assertThat(Bytes.toString(table.get(get2).list().get(0).getValue()),is("一叶渡江"));
//更新nickname为yedu
Put put2 = new Put(Bytes.toBytes("1")); :
put2.add(Bytes.toBytes("author"), Bytes.toBytes("nickname"), Bytes.toBytes("yedu"));
table.put(put2);
//查询更新结果
Get get3 = new Get(Bytes.toBytes("1"));
get3.addColumn(Bytes.toBytes("author"), Bytes.toBytes("nickname"));
assertThat(Bytes.toString(table.get(get3).list().get(0).getValue()),is("yedu"));
//查询nickname的多个(本示例为2个)版本值
Get get4 = new Get(Bytes.toBytes("1"));
get4.addColumn(Bytes.toBytes("author"), Bytes.toBytes("nickname"));
get4.setMaxVersions(2);
List results = table.get(get4).list();
assertThat(results.size(),is(2));
assertThat(Bytes.toString(results.get(0).getValue()),is("yedu"));
assertThat(Bytes.toString(results.get(1).getValue()),is("一叶渡江"));
/**=========删除记录=========*/
//删除指定column
Delete deleteColumn = new Delete(Bytes.toBytes("1"));
deleteColumn.deleteColumns(Bytes.toBytes("author"),Bytes.toBytes("nickname"));
table.delete(deleteColumn);
assertThat( table.get(get4).list(),nullValue());
//删除所有column
Delete deleteAll = new Delete(Bytes.toBytes("1"));
table.delete(deleteAll);
assertThat(table.getScanner(scan).next(),nullValue());
/**=========删除表=========*/
admin.disableTable("blog");
admin.deleteTable("blog");
assertThat(admin.tableExists("blog"),is(false));
}
}












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