Example usage for java.nio.file StandardOpenOption SPARSE

Introduction

In this page you can find the example usage for java.nio.file StandardOpenOption SPARSE.

Prototype

StandardOpenOption SPARSE

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Document

Sparse file.

Usage

From source file:com.netflix.genie.web.services.impl.DiskJobFileServiceImpl.java

/**
 * {@inheritDoc}/*from w  ww.  ja v  a2  s  .  co m*/
 */
@Override
// TODO: We should be careful about how large the byte[] is. Perhaps we should have precondition to protect memory
//       or we should wrap calls to this in something that chunks it off an input stream or just take this in as
//       input stream
public void updateFile(final String jobId, final String relativePath, final long startByte, final byte[] data)
        throws IOException {
    log.debug("Attempting to write {} bytes from position {} into log file {} for job {}", data.length,
            startByte, relativePath, jobId);
    final Path jobFile = this.jobsDirRoot.resolve(jobId).resolve(relativePath);

    if (Files.notExists(jobFile)) {
        // Make sure all the directories exist on disk
        final Path logFileParent = jobFile.getParent();
        if (logFileParent != null) {
            this.createOrCheckDirectory(logFileParent);
        }
    } else if (Files.isDirectory(jobFile)) {
        // TODO: Perhaps this should be different exception
        throw new IllegalArgumentException(relativePath + " is a directory not a file. Unable to update");
    }

    try (FileChannel fileChannel = FileChannel.open(jobFile,
            EnumSet.of(StandardOpenOption.CREATE, StandardOpenOption.WRITE, StandardOpenOption.SPARSE))) {
        // Move the byteChannel to the start byte
        fileChannel.position(startByte);

        // The size and length are ignored in this implementation as we just assume we're writing everything atm
        // TODO: Would it be better to provide an input stream and buffer the output?
        final ByteBuffer byteBuffer = ByteBuffer.wrap(data);

        while (byteBuffer.hasRemaining()) {
            fileChannel.write(byteBuffer);
        }
    }
}

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From source file:org.neo4j.io.pagecache.PageCacheTest.java

@Test(timeout = SEMI_LONG_TIMEOUT_MILLIS)
public void mustIgnoreCertainOpenOptions() throws Exception {
    getPageCache(fs, maxPages, pageCachePageSize, PageCacheTracer.NULL);
    try (PagedFile pf = pageCache.map(file("a"), filePageSize, StandardOpenOption.READ,
            StandardOpenOption.WRITE, StandardOpenOption.APPEND, StandardOpenOption.SPARSE);
            PageCursor cursor = pf.io(0, PF_SHARED_WRITE_LOCK)) {
        assertTrue(cursor.next());//from w  ww. ja  v a 2s .  co m
    }
}

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