File	Doc	Category	Size	Date	Package
MappedByteBuffer.java	API Doc	Java SE 5 API	5763	Fri Aug 26 14:57:10 BST 2005	java.nio

MappedByteBuffer

• java.lang.Object
  • java.nio.Buffer
    • java.nio.ByteBuffer

Fields Summary
volatile boolean	isAMappedBuffer

Constructors Summary
MappedByteBuffer(int mark, int pos, int lim, int cap, boolean mapped) super(mark, pos, lim, cap); isAMappedBuffer = mapped;
MappedByteBuffer(int mark, int pos, int lim, int cap) // package-private super(mark, pos, lim, cap); isAMappedBuffer = false;

Methods Summary
private void	checkMapped() if (!isAMappedBuffer) // Can only happen if a luser explicitly casts a direct byte buffer throw new UnsupportedOperationException();
public final java.nio.MappedByteBuffer	force() Forces any changes made to this buffer's content to be written to the storage device containing the mapped file. If the file mapped into this buffer resides on a local storage device then when this method returns it is guaranteed that all changes made to the buffer since it was created, or since this method was last invoked, will have been written to that device. If the file does not reside on a local device then no such guarantee is made. If this buffer was not mapped in read/write mode ({@link java.nio.channels.FileChannel.MapMode#READ_WRITE}) then invoking this method has no effect. return This buffer checkMapped(); if ((address == 0) || (capacity() == 0)) return this; force0(((DirectByteBuffer)this).address(), capacity()); return this;
private native void	force0(long address, long length)
public final boolean	isLoaded() Tells whether or not this buffer's content is resident in physical memory. A return value of true implies that it is highly likely that all of the data in this buffer is resident in physical memory and may therefore be accessed without incurring any virtual-memory page faults or I/O operations. A return value of false does not necessarily imply that the buffer's content is not resident in physical memory. The returned value is a hint, rather than a guarantee, because the underlying operating system may have paged out some of the buffer's data by the time that an invocation of this method returns. return true if it is likely that this buffer's content is resident in physical memory checkMapped(); if ((address == 0) || (capacity() == 0)) return true; return isLoaded0(((DirectByteBuffer)this).address(), capacity());
private native boolean	isLoaded0(long address, long length)
public final java.nio.MappedByteBuffer	load() Loads this buffer's content into physical memory. This method makes a best effort to ensure that, when it returns, this buffer's content is resident in physical memory. Invoking this method may cause some number of page faults and I/O operations to occur. return This buffer checkMapped(); if ((address == 0) || (capacity() == 0)) return this; load0(((DirectByteBuffer)this).address(), capacity(), Bits.pageSize()); return this;
private native int	load0(long address, long length, int pageSize)