HDFS-17767. Skip tests that depend on custom SecurityManager when Java doesn't support it

Closes #7566

Co-authored-by: Tsz-Wo Nicholas Sze <szetszwo@apache.org>
Signed-off-by: Chris Nauroth <cnauroth@apache.org>

hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/TestDFSShell.java

@@ -19,7 +19,6 @@ package org.apache.hadoop.hdfs;
 
 import java.io.*;
 import java.nio.charset.StandardCharsets;
-import java.security.Permission;
 import java.security.PrivilegedExceptionAction;
 import java.text.SimpleDateFormat;
 import java.util.ArrayList;
@@ -49,6 +48,7 @@ import org.apache.hadoop.fs.*;
 import org.apache.hadoop.fs.permission.AclEntry;
 import org.apache.hadoop.fs.permission.FsPermission;
 import org.apache.hadoop.hdfs.client.HdfsClientConfigKeys;
+import org.apache.hadoop.hdfs.protocol.AlreadyBeingCreatedException;
 import org.apache.hadoop.hdfs.protocol.Block;
 import org.apache.hadoop.hdfs.protocol.BlockListAsLongs;
 import org.apache.hadoop.hdfs.protocol.ExtendedBlock;
@@ -61,6 +61,7 @@ import org.apache.hadoop.io.SequenceFile;
 import org.apache.hadoop.io.Text;
 import org.apache.hadoop.io.compress.BZip2Codec;
 import org.apache.hadoop.io.compress.CompressionCodec;
+import org.apache.hadoop.ipc.RemoteException;
 import org.apache.hadoop.net.ServerSocketUtil;
 import org.apache.hadoop.security.UserGroupInformation;
 import org.apache.hadoop.test.GenericTestUtils;
@@ -556,52 +557,24 @@ public class TestDFSShell {
     final Path root = mkdir(dfs, new Path("/testPut"));
     final Path dst = new Path(root, "dst");
 
-    show("begin");
-
-    final Thread copy2ndFileThread = new Thread() {
-      @Override
-      public void run() {
-        try {
-          show("copy local " + f2 + " to remote " + dst);
-          dfs.copyFromLocalFile(false, false, new Path(f2.getPath()), dst);
-        } catch (IOException ioe) {
-          show("good " + StringUtils.stringifyException(ioe));
-          return;
-        }
-        //should not be here, must got IOException
-        assertTrue(false);
-      }
-    };
-
-    //use SecurityManager to pause the copying of f1 and begin copying f2
-    SecurityManager sm = System.getSecurityManager();
-    System.out.println("SecurityManager = " + sm);
-    System.setSecurityManager(new SecurityManager() {
-      private boolean firstTime = true;
-
-      @Override
-      public void checkPermission(Permission perm) {
-        if (firstTime) {
-          Thread t = Thread.currentThread();
-          if (!t.toString().contains("DataNode")) {
-            String s = "" + Arrays.asList(t.getStackTrace());
-            if (s.contains("FileUtil.copyContent")) {
-              //pause at FileUtil.copyContent
-
-              firstTime = false;
-              copy2ndFileThread.start();
-              try {Thread.sleep(5000);} catch (InterruptedException e) {}
-            }
-          }
-        }
+    final String hello = "hello";
+    try (FSDataOutputStream out = dfs.create(dst, false)) {
+    // It should fail to create a new client writing to the same file.
+      try(DFSClient client = new DFSClient(dfs.getUri(), dfs.getConf())) {
+        final RemoteException e = Assert.assertThrows(RemoteException.class,
+            () -> client.create(dst.toString(), false));
+        LOG.info("GOOD", e);
+        Assert.assertEquals(e.getClassName(), AlreadyBeingCreatedException.class.getName());
       }
-    });
-    show("copy local " + f1 + " to remote " + dst);
-    dfs.copyFromLocalFile(false, false, new Path(f1.getPath()), dst);
-    show("done");
+      // It should succeed to continue writing to the file.
+      out.writeUTF(hello);
+     }
 
-    try {copy2ndFileThread.join();} catch (InterruptedException e) { }
-    System.setSecurityManager(sm);
+    // Verify the file content.
+    try (FSDataInputStream in = dfs.open(dst)) {
+      final String read = in.readUTF();
+      assertEquals(hello, read);
+    }
 
     // copy multiple files to destination directory
     final Path destmultiple = mkdir(dfs, new Path(root, "putmultiple"));

hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/TestDatanodeRegistration.java

@@ -48,6 +48,7 @@ import java.security.Permission;
 import java.util.concurrent.TimeoutException;
 
 import static org.junit.Assert.*;
+import static org.junit.Assume.assumeTrue;
 import static org.mockito.Mockito.doReturn;
 import static org.mockito.Mockito.mock;
 
@@ -79,8 +80,12 @@ public class TestDatanodeRegistration {
   @Test
   public void testDNSLookups() throws Exception {
     MonitorDNS sm = new MonitorDNS();
-    System.setSecurityManager(sm);
-    
+    try {
+      System.setSecurityManager(sm);
+    } catch (UnsupportedOperationException e) {
+      assumeTrue("Test is skipped because SecurityManager cannot be set (JEP 411)", false);
+    }
+
     MiniDFSCluster cluster = null;
     try {
       HdfsConfiguration conf = new HdfsConfiguration();