第二十七讲.动态设置相关参数(replication为2和blocksize为10字节)

视频：【美妙人生】Hadoop课程系列之HDFS–手把手教你精通HDFS

【美妙人生】Hadoop课程系列之HDFS–手把手教你精通HDFS

【视频笔记】

通过java.net.URL类访问写入HDFS数据
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?? ?
?? ?@Test
?? ?public void writeByURL() throws Exception {
?? ??? ?URL _url ?=new URL("hdfs://master1:9000/spaceQuota/hello.txt");
?? ??? ?URLConnection conn = _url.openConnection();
?? ??? ?OutputStream out = conn.getOutputStream();
?? ??? ?out.write("hello world".getBytes());
?? ??? ?out.close();
?? ?} ? ?

通过FileSystem API做write操作
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? ?
?? ?@Test
?? ?public void ?writeByAPI() throws IOException{
?? ??? ?Configuration conf = new Configuration();
?? ??? ?FileSystem fs ?=FileSystem.get(conf);
?? ??? ?Path file = new Path("/spaceQuota/hello.txt");
?? ??? ?FSDataOutputStream out = fs.create(file);
?? ??? ?out.write("hello world".getBytes());
?? ??? ?out.close();
?? ?}

通过FileSystem API做写操作,动态设置相关参数:replication为2和blocksize为10字节
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 ?
?? ?@Test
?? ?public void writeByAPIForBlocksize() throws IOException{
?? ??? ?Configuration conf = new Configuration();
?? ??? ?conf.set("fs.defaultFS", "hdfs://master1:9000");
?? ??? ?conf.set("dfs.bytes-per-checksum", "10");
?? ??? ?FileSystem fs ?=FileSystem.get(conf);
?? ??? ?Path file = new Path("/spaceQuota/hello6666.txt");
?? ??? ?FSDataOutputStream out = fs.create(file, true, 4096,(short)2, 10);
?? ??? ?out.write("hello world".getBytes());
?? ??? ?out.close();
?? ?}