public class Test {
private static Configuration conf;
private static FileSystem fs;
//开启kerberos认证
static {
System.setProperty("java.security.krb5.conf", "D:\HDFS-test\krb5.conf");
conf=new Configuration();
conf.addResource(new Path("D:\HDFS-test\hdfs-site.xml"));
conf.set("hadoop.security.authentication", "kerberos"); //配置认证方式
conf.set("fs.default.name", "hdfs://172.20.237.112:8020");//namenode的地址和端口
UserGroupInformation.setConfiguration(conf);
try {
UserGroupInformation.loginUserFromKeytab("hdfs/gz237-112", "D:\HDFS-test\hdfs.keytab");
} catch (IOException e) {
e.printStackTrace();
}
}
/**
* 未开启安全
*/
// static {
// conf = new Configuration();
// ip为Namenode master所在节点
// conf.set("fs.default.name", "hdfs://172.20.237.112:8020");
// FileSystem类在hadoop-hdfs包中
// conf.set("fs.hdfs.impl", org.apache.hadoop.hdfs.DistributedFileSystem.class.getName());
// }
public static void main(String[] args) throws Exception {
// mkdirCatalog("/yfb");//在hdfs上创建目录
putfile("D:\test.txt", "/yfb");//上传文件
// createFile("/data.txt");//在hdfs上创建文件
// deleteFile("/data.txt");//删除HDFS上的文件
// downloadFile("/dddd1111.txt","D:\");//文件下载
}
//1、创建目录
public static void mkdirCatalog(String path) throws Exception{
//创建连接，使用开源的进行，连接报错
Caused by: java.net.ConnectException: Connection refused: no further information at sun.nio.ch.SocketChannelImpl.checkConnect(Native Method) at sun.nio.ch.SocketChannelImpl.finishConnect(SocketChannelImpl.java:717) at org.apache.hadoop.net.SocketIOWithTimeout.connect(SocketIOWithTimeout.java:206)
// FileSystem fs = FileSystem.get(URI.create("hdfs://172.20.237.112:9000"),conf);
//TDH的方式
fs = FileSystem.get(conf);
fs.mkdirs(new Path(path));
}
//上传文件到hdfs
public static void putfile(String localfile,String hdfsfile) throws IOException {
fs = FileSystem.get(conf);
fs.copyFromLocalFile(new Path(localfile),new Path(hdfsfile));
}
//HDFS上创建文件
public static void createFile(String path) throws Exception {
fs = FileSystem.get(conf);
fs.createNewFile(new Path(path));
}
//删除HDFS上的文件
public static void deleteFile(String path) throws Exception {
fs = FileSystem.get(conf);
if(fs.exists(new Path(path))){
fs.delete(new Path(path),true);
}else {
System.out.println("您所删除的文件不存在！");
}
}
//下载文件到本地
public static void downloadFile(String hdfsPath,String localPath) throws Exception {
fs = FileSystem.get(conf);
fs.copyToLocalFile(new Path(hdfsPath),new Path(localPath));
}
}