import java.io.IOException;
import java.io.InputStream;
import java.util.List;
import java.util.Map;
import org.apache.commons.io.IOUtils;
import org.apache.commons.lang3.StringUtils;
import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.fs.FileSystem;
import org.apache.hadoop.fs.Path;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import com.google.common.collect.Maps;
public class LoadHdfsTemplate {
static final Logger logger = LoggerFactory
.getLogger(LoadHdfsTemplate.class);
protected FileSystem fileSystem ;
private String hdfsPath = "/template/template.txt";
public final boolean checkFile(String filePath) {
boolean exists = false;
try {
Path path = new Path(filePath);
exists = fileSystem.exists(path);
} catch (IOException e) {
logger.error("接口模板文件不存在!", e);
} catch (Exception e) {
logger.error("", e);
}
return exists;
}
public Map<String,Object> readHdfsFile() throws IOException{
fileSystem = FileSystem.get(new Configuration());
Path path = new Path(hdfsPath);
InputStream in = fileSystem.open(path);
List<String> lines = IOUtils.readLines(in);
if(null == lines || lines.isEmpty()){
return null;
}
Map<String,Object> map = Maps.newConcurrentMap();
int rowNum = 0;
for(String line : lines){
rowNum++;
String[] content = line.split(" ");
String code = content[0].trim();
String template = content[1].trim();
if(StringUtils.isEmpty(line) || StringUtils.isEmpty(template)){
logger.error("第{}条模板格式错误!内容为:{}",rowNum,line);
continue;
}
map.put(code, template);
}
return map;
}
public void setHdfsPath(String hdfsPath) {
this.hdfsPath = hdfsPath;
}
}
应用场景为,读取hdfs上的文件,并转化成<k,v>形式存入内存。