http://blog.csdn.net/karen_wang/archive/2011/03/28/6284154.aspx
1、需要的jar包:
commons-codec-1.4.jar
commons-logging-1.0.4.jar
hadoop-0.20.2-core.jar
hbase-0.20.6.jar
log4j-1.2.15.jar
zookeeper-3.2.2.jar
2、已有表结构:
1、表名:scores
2、列族:
course:art
course:math
grade:
3、scan 'scores'的内容:
ROW COLUMN+CELL
Jerry column=course:art, timestamp=1301294630194, value=80
Jerry column=course:math, timestamp=1301294630132, value=100
Jerry column=grade:, timestamp=1301294630073, value=2
Jim column=course:art, timestamp=1301294630363, value=97
Jim column=course:math, timestamp=1301294630305, value=100
Jim column=grade:, timestamp=1301294630247, value=3
Tom column=course:art, timestamp=1301294630015, value=97
Tom column=course:math, timestamp=1301294629987, value=87
Tom column=grade:, timestamp=1301294629931, value=1
4、代码:
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package org.myhbase;
import java.io.IOException;
import java.util.ArrayList;
import java.util.List;
import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.hbase.HBaseConfiguration;
import org.apache.hadoop.hbase.KeyValue;
import org.apache.hadoop.hbase.client.Get;
import org.apache.hadoop.hbase.client.HTable;
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.FilterList;
import org.apache.hadoop.hbase.filter.SingleColumnValueFilter;
import org.apache.hadoop.hbase.filter.CompareFilter.CompareOp;
import org.apache.hadoop.hbase.io.Cell;
import org.apache.hadoop.hbase.util.Bytes;
public class HBaseBasic03 {
private static HBaseConfiguration hbaseConfig=null;
static{
Configuration config=new Configuration();
config.set("hbase.zookeeper.quorum","192.168.10.149,192.168.10.44,192.168.10.49");
config.set("hbase.zookeeper.property.clientPort", "2181");
hbaseConfig=new HBaseConfiguration(config);
}
/**
* get方式,通过rowKey查询
* @param tablename
* @param rowKey
* @throws IOException
*/
public static void selectByRowKey(String tablename,String rowKey) throws IOException{
HTable table=new HTable(hbaseConfig,tablename);
Get g = new Get(Bytes.toBytes(rowKey));
Result r=table.get(g);
for(KeyValue kv:r.raw()){
System.out.println("column: "+new String(kv.getColumn()));
System.out.println("value: "+new String(kv.getValue()));
}
}
/**
* get方式,通过rowKey、column查询
* @param tablename
* @param rowKey
* @param column
* @throws IOException
*/
public static void selectByRowKeyColumn(String tablename,String rowKey,String column) throws IOException{
HTable table=new HTable(hbaseConfig,tablename);
Get g = new Get(Bytes.toBytes(rowKey));
g.addColumn(Bytes.toBytes(column));
Result r=table.get(g);
for(KeyValue kv:r.raw()){
System.out.println("column: "+new String(kv.getColumn()));
System.out.println("value: "+new String(kv.getValue()));
}
}
public static void selectByFilter(String tablename,List<String> arr) throws IOException{
HTable table=new HTable(hbaseConfig,tablename);
FilterList filterList = new FilterList();
Scan s1 = new Scan();
for(String v:arr){ // 各个条件之间是“与”的关系
String [] s=v.split(",");
filterList.addFilter(new SingleColumnValueFilter(Bytes.toBytes(s[0]),
Bytes.toBytes(s[1]),
CompareOp.EQUAL,Bytes.toBytes(s[2])
)
);
// 添加下面这一行后,则只返回指定的cell,同一行中的其他cell不返回
// s1.addColumn(Bytes.toBytes(s[0]), Bytes.toBytes(s[1]));
}
s1.setFilter(filterList);
ResultScanner ResultScannerFilterList = table.getScanner(s1);
for(Result rr=ResultScannerFilterList.next();rr!=null;rr=ResultScannerFilterList.next()){
for(KeyValue kv:rr.list()){
System.out.println("row : "+new String(kv.getRow()));
System.out.println("column : "+new String(kv.getColumn()));
System.out.println("value : "+new String(kv.getValue()));
}
}
}
public static void main(String [] args) throws IOException{
// 按rowkey查询,查询Tom行的所有cell
HBaseBasic03.selectByRowKey("scores","Tom");
// 按rokey 和 column 来查询,查询Tom行course列族的所有列值
HBaseBasic03.selectByRowKeyColumn("scores","Tom","course");
// Filter多条件查询,条件:查询 course列族中art列值为97 ,且 course列族中math列值为100的行
List<String> arr=new ArrayList<String>();
arr.add("course,art,97");
arr.add("course,math,100");
HBaseBasic03.selectByFilter("scores",arr);
}
}