dn.length == 1);
LocatedBlocks locations = client.getNamenode().getBlockLocations(
file1.toString(), 0, Long.MAX_VALUE);
List<LocatedBlock> blocks = locations.getLocatedBlocks();
FSDataset dataset = (FSDataset) dn[0].data;
//
// Create hard links for a few of the blocks
//
for (int i = 0; i < blocks.size(); i = i + 2) {
ExtendedBlock b = blocks.get(i).getBlock();
File f = dataset.getFile(b.getBlockPoolId(), b.getLocalBlock());
File link = new File(f.toString() + ".link");
System.out.println("Creating hardlink for File " + f + " to " + link);
HardLink.createHardLink(f, link);
}
//
// Detach all blocks. This should remove hardlinks (if any)
//
for (int i = 0; i < blocks.size(); i++) {
ExtendedBlock b = blocks.get(i).getBlock();
System.out.println("testCopyOnWrite detaching block " + b);
assertTrue("Detaching block " + b + " should have returned true",
dataset.unlinkBlock(b, 1));
}
// Since the blocks were already detached earlier, these calls should
// return false
//
for (int i = 0; i < blocks.size(); i++) {
ExtendedBlock b = blocks.get(i).getBlock();
System.out.println("testCopyOnWrite detaching block " + b);
assertTrue("Detaching block " + b + " should have returned false",
!dataset.unlinkBlock(b, 1));
}
} finally {
fs.close();
cluster.shutdown();