aeron-samples/src/main/java/io/aeron/samples/SamplesUtil.java
public static MappedByteBuffer mapExistingFileReadOnly(final File location)
    {
        if (!location.exists())
        {
            final String msg = "file not found: " + location.getAbsolutePath();
            throw new IllegalStateException(msg);
        }

        MappedByteBuffer mappedByteBuffer = null;
        try (RandomAccessFile file = new RandomAccessFile(location, "r");
            FileChannel channel = file.getChannel())
        {
            mappedByteBuffer = channel.map(READ_ONLY, 0, channel.size());
        }
        catch (final IOException ex)
        {
            LangUtil.rethrowUnchecked(ex);
        }

        return mappedByteBuffer;
    }
public static MappedByteBuffer mapExistingFileReadOnly(final File location)
    {
        if (!location.exists())
        {
            final String msg = "file not found: " + location.getAbsolutePath();
            throw new IllegalStateException(msg);
        }

        MappedByteBuffer mappedByteBuffer = null;
        try (RandomAccessFile file = new RandomAccessFile(location, "r");
            FileChannel channel = file.getChannel())
        {
            mappedByteBuffer = channel.map(READ_ONLY, 0, channel.size());
        }
        catch (final IOException ex)
        {
            LangUtil.rethrowUnchecked(ex);
        }

        return mappedByteBuffer;
    }
public static MappedByteBuffer mapExistingFileReadOnly ( final File location ) { if ( ! location . exists ( ) ) { final String msg = "file not found: " + location . getAbsolutePath ( ) ; throw new IllegalStateException ( msg ) ; } MappedByteBuffer mappedByteBuffer = null ; try ( RandomAccessFile file = new RandomAccessFile ( location , "r" ) ; FileChannel channel = file . getChannel ( ) ) { mappedByteBuffer = channel . map ( READ_ONLY , 0 , channel . size ( ) ) ; } catch ( final IOException ex ) { LangUtil . rethrowUnchecked ( ex ) ; } return mappedByteBuffer ; }
Map an existing file as a read only buffer.

@param location of file to map.
@return the mapped file.
Map an existing file as a read only buffer .