1 //查看文件信息
2 //cathdfs("");
3 //查看文件内容
4 //readfile("");
5 //创建空一个文件
6 //createfile("");
7 //创建一个文件并写入文件内容
8 //cufile("");
9 //创建一个文件夹
10 //mkdirfile("");
11 //重名称文件或文件夹
12 //renameFile("");
13 //删除文件或文件夹
14 //deletefile("");
15 //上传HDFS
16 //uploadfile("","");
17 //下载到本地
18 //downloadfile("","");
1 //查询文件信息
2 public static void cathdfs(String path){
3 //创建连接uri
4 String uri="hdfs://192.168.152.131:9000/";
5 //实例化配置文件对象
6 Configuration con=new Configuration();
7 FileSystem fileSystem=null;
8 FileStatus fileStatus=null;
9 try {
10 //创建文件系统对象，指定文件的操作
11 fileSystem=FileSystem.get(URI.create(uri),con);
12 //获取单个文件信息系
13 fileStatus=fileSystem.getFileStatus(new Path(path));
14 System.out.print(fileStatus);
15
16 System.out.print("========================================分割线");
17 /**
18 * 查询所有与文件信息
19 */
20 FileStatus[] listStatus= fileSystem.listStatus(new Path(path));
21 for(FileStatus staus:listStatus){
22 System.out.println(staus);
23 }
24 } catch (IOException e) {
25
26 e.printStackTrace();
27 }finally{
28 try {
29 fileSystem.close();
30 } catch (IOException e) {
31 e.printStackTrace();
32 }
33 }
34
35 }
1 //查询文件内容
2 public static void readfile(String fileName){
3 //第一步创建url链接
4 String uri="hdfs://192.168.152.131:9000/";
5 //第二步实例化配置文件对象
6 Configuration config=new Configuration();
7 //第三步创建文件系统对象，实现对文件到的操作,创建出入流对象
8 FileSystem fileSystem=null;
9 FSDataInputStream input=null;
10 BufferedReader br=null;
11 try {
12 //第四步 使用
13 fileSystem=FileSystem.get(URI.create(uri),config);
14 input=fileSystem.open(new Path(fileName));
15 br=new BufferedReader(new InputStreamReader(input));
16 String line="";
17 while((line=br.readLine())!=null){
18 System.out.print(line);
19 }
20 } catch (IOException e) {
21 e.printStackTrace();
22 }finally{
23 try {
24 //第五步关闭资源
25 br.close();
26 input.close();
27 fileSystem.close();
28 } catch (IOException e) {
29
30 e.printStackTrace();
31 }
32 }
33
34 }
1 //创建一个空的文件
2 public static void createfile(String filename){
3 //一
4 String uri="hdfs://192.168.152.131:9000/";
5 //二
6 Configuration con=new Configuration();
7 //三
8 FileSystem file=null;
9 try {
10 file=FileSystem.get(URI.create(uri),con);
11 boolean fase=file.createNewFile(new Path(filename));
12 if(fase){
13 System.out.print("成功");
14 }else{
15 System.out.print("失败");
16 }
17 } catch (IOException e) {
18
19 e.printStackTrace();
20 }finally{
21 try {
22 //四
23 file.close();
24 } catch (IOException e) {
25 e.printStackTrace();
26 }
27 }
28 }
1 //创建一个空文件并写入文件
2 public static void cufile(String filename){
3 //1
4 String uri="hdfs://192.168.152.131:9000/";
5 //2
6 Configuration con=new Configuration();
7 //3
8 FileSystem fiel=null;
9 FSDataOutputStream fs=null;
10 try {
11 fiel=FileSystem.get(URI.create(uri),con);
12 if(fiel.exists(new Path(filename))){
13 //文件已经存在
14 System.out.println("文件已经存在");
15 }else{
16 //文件不存在
17 fs= fiel.create(new Path(filename));
18 //文件内容
19 String str="呵呵";
20 fs.write(str.getBytes());
21 fs.flush();
22 }
23 } catch (IOException e) {
24
25 e.printStackTrace();
26 }finally{
27 try {
28 //4
29 fs.close();
30 fiel.close();
31 } catch (IOException e) {
32
33 e.printStackTrace();
34 }
35 }
36 }
1 //创建一个文件夹
2 public static void mkdirfile(String filename){
3 //1
4 String uri="hdfs://192.168.152.131:9000/";
5 //2
6 Configuration con=new Configuration();
7 //3
8 FileSystem file=null;
9 try {
10 file=FileSystem.get(URI.create(uri),con);
11 boolean mkdirs = file.mkdirs(new Path(filename));
12 if(mkdirs){
13 System.out.print("成功");
14 }else{
15 System.out.print("失败");
16 }
17 } catch (IOException e) {
18
19 e.printStackTrace();
20 }finally{
21 try {
22 //4
23 file.close();
24 } catch (IOException e) {
25
26 e.printStackTrace();
27 }
28 }
29 }
30
1 //重命名文件或文件夹
2 public static void renameFile(String oldname,String filename){
3 //1
4 String uri="hdfs://192.168.152.131:9000/";
5 //2
6 Configuration con=new Configuration();
7 //3
8 FileSystem file=null;
9 try {
10 file=FileSystem.get(URI.create(uri),con);
11 //1.文件或文件夹原名称 2.修改文件或文件夹名称
12 boolean rename = file.rename(new Path(oldname), new Path(filename));
13 if(rename){
14 System.out.print("成功");
15 }else{
16 System.out.print("失败");
17 }
18 } catch (IOException e) {
19
20 e.printStackTrace();
21 }finally{
22 try {
23 file.close();
24 } catch (IOException e) {
25
26 e.printStackTrace();
27 }
28 }
29
30 }
31
1 //删除文件或文件夹
2 public static void deletefile(String filename){
3 //1
4 String uri="hdfs://192.168.152.131:9000/";
5 //2
6 Configuration con=new Configuration();
7 //3
8 FileSystem file=null;
9 try {
10 file=FileSystem.get(URI.create(uri),con);
11 boolean delete = file.delete(new Path(filename));
12 if(delete){
13 System.out.print("成功");
14 }else{
15 System.out.print("失败");
16 }
17 } catch (IOException e) {
18
19 e.printStackTrace();
20 }finally{
21 try {
22 file.close();
23 } catch (IOException e) {
24
25 e.printStackTrace();
26 }
27 }
28 }
1 //本地文件上传到HDFS
2 public static void uploadfile(String loadfile,String desfile){
3 //1
4 String uri="hdfs://192.168.152.131:9000/";
5 //2
6 Configuration con=new Configuration();
7 //3
8 FileSystem file=null;
9 try {
10 file=FileSystem.get(URI.create(uri),con);
11 //上传中
12 file.copyFromLocalFile(new Path(loadfile), new Path(desfile));
13 } catch (IOException e) {
14
15 e.printStackTrace();
16 }finally{
17 try {
18 file.close();
19 } catch (IOException e) {
20
21 e.printStackTrace();
22 }
23 }
24 System.out.println("上传中---------");
25 }
1 //HDFS下载文件到本地
2 public static void downloadfile(String desfile,String loadfile){
3 //1
4 String uri="";
5 //2
6 Configuration con=new Configuration();
7 //3
8 FileSystem file=null;
9 try {
10 file=FileSystem.get(URI.create(uri),con);
11 //下载中
12 file.copyToLocalFile(new Path(desfile), new Path(loadfile));
13 } catch (IOException e) {
14
15 e.printStackTrace();
16 }finally{
17 try {
18 file.close();
19 } catch (IOException e) {
20
21 e.printStackTrace();
22 }
23 }
24 System.out.println("下载中-----------");
25 }
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