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public class HdfsUtil {
private FileSystem fs = null;
@Before
public void init() throws Exception {
//读取classpath下的core-site.xml配置文件
Configuration conf = new Configuration();
//手动封装配置中需要读取的信息
conf.set("fs.defaultFS", "hdfs://192.168.2.100:9000");
//根据配置信息获取一个具体的客户端实例对象
fs = FileSystem.get(new URI("hdfs://192.168.2.100:9000"), conf, "hadoop");
}
@Test
//通过流上传文件
public void uploadByStream() throws IOException {
Path path = new Path("hdfs://192.168.2.100:9000/user/hadoop/mark.txt");
FSDataOutputStream dataOut = fs.create(path);
FileInputStream dataIn = new FileInputStream("c://mark.txt");
IOUtils.copy(dataIn, dataOut);
}
@Test
//通过封装好方法上传文件
public void uploadByMethods() throws IOException {
fs.copyFromLocalFile(new Path("c://mark.txt"), new Path("hdfs://192.168.2.100:9000/user/hadoop/mark.txt"));
}
@Test
//下载文件
public void download() throws IOException {
fs.copyToLocalFile(new Path("hdfs://192.168.2.100:9000/user/hadoop/mark.txt"),new Path("d://JAVA"));
}
@Test
//查看文件
public void listFiles() throws IOException {
RemoteIteratorfiles = fs.listFiles(new Path("/"), true);
while (files.hasNext()){
LocatedFileStatus file = files.next();
Path path = file.getPath();
System.out.println(path.getName());
}
System.out.println("------------------");
FileStatus[] fileStatuses = fs.listStatus(new Path("/"));
for (FileStatus fileStatus : fileStatuses){
String name = fileStatus.getPath().getName();
System.out.println(name);
}
}
@Test
//创建文件夹
public void mkdir() throws IOException {
fs.mkdirs(new Path("/user/mark"));
}
@Test
//删除文件或文件下
public void rm() throws IOException {
fs.delete(new Path("/user/mark"),true);
}
}
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