以遍历的形式读取HBase数据库

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package com.bdms.hbase.app;

import java.io.IOException;

@Service("hbaseAppService")
public class HbaseAppServiceImpl implements HbaseAppService {

//@Autowired
//private HbaseAppService hbaseappservice;

//@Autowired
//private Hbaseconfig hc ;

private ConfigEntry entry = Hbaseconfig.getConfigEntry();

public  List<Map<String,String>> getAlldata(HTable hTable,Map<String, List<String>> columns,int num) throws IOException {


List<Map<String,String>>  res = new ArrayList<Map<String,String>>();
Map<String,String> row = null;

Scan scan=new Scan();

Set<String> keySet = columns.keySet();

scan.setCaching(1000);
for(String fn : keySet){
for(String cf : columns.get(fn)){
scan.addColumn(fn.getBytes(), cf.getBytes());
}
}

  final ResultScanner scanner=hTable.getScanner(scan);
 
int i=0;


for(Result result1 : scanner){

if(num > 0 )
{
if(i==num) break;
   i++;
}

row = new HashMap<String, String>();

for(String fn : keySet){
for(String cf : columns.get(fn)){
row.put(cf,new String(result1.getValue(fn.getBytes(), cf.getBytes())) );
 
}
}
res.add(row);
  
}
return res;


}



}
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