Package org.apache.lucene.store
Class IndexOutput
- java.lang.Object
-
- org.apache.lucene.store.DataOutput
-
- org.apache.lucene.store.IndexOutput
-
- All Implemented Interfaces:
Closeable,AutoCloseable
- Direct Known Subclasses:
ByteBuffersIndexOutput,FilterIndexOutput,OutputStreamIndexOutput
public abstract class IndexOutput extends DataOutput implements Closeable
ADataOutputfor appending data to a file in aDirectory.Instances of this class are not thread-safe.
- See Also:
Directory,IndexInput
-
-
Constructor Summary
Constructors Modifier Constructor Description protectedIndexOutput(String resourceDescription, String name)Sole constructor.
-
Method Summary
All Methods Static Methods Instance Methods Abstract Methods Concrete Methods Modifier and Type Method Description longalignFilePointer(int alignmentBytes)Aligns the current file pointer to multiples ofalignmentBytesbytes to improve reads with mmap.static longalignOffset(long offset, int alignmentBytes)Aligns the givenoffsetto multiples ofalignmentBytesbytes by rounding up.abstract voidclose()Closes this stream to further operations.abstract longgetChecksum()Returns the current checksum of bytes written so farabstract longgetFilePointer()Returns the current position in this file, where the next write will occur.StringgetName()Returns the name used to create thisIndexOutput.StringtoString()-
Methods inherited from class org.apache.lucene.store.DataOutput
copyBytes, writeByte, writeBytes, writeBytes, writeGroupVInts, writeInt, writeLong, writeMapOfStrings, writeSetOfStrings, writeShort, writeString, writeVInt, writeVLong, writeZInt, writeZLong
-
-
-
-
Constructor Detail
-
IndexOutput
protected IndexOutput(String resourceDescription, String name)
Sole constructor. resourceDescription should be non-null, opaque string describing this resource; it's returned fromtoString().
-
-
Method Detail
-
getName
public String getName()
Returns the name used to create thisIndexOutput. This is especially useful when usingDirectory.createTempOutput(java.lang.String, java.lang.String, org.apache.lucene.store.IOContext).
-
close
public abstract void close() throws IOExceptionCloses this stream to further operations.- Specified by:
closein interfaceAutoCloseable- Specified by:
closein interfaceCloseable- Throws:
IOException
-
getFilePointer
public abstract long getFilePointer()
Returns the current position in this file, where the next write will occur.
-
getChecksum
public abstract long getChecksum() throws IOExceptionReturns the current checksum of bytes written so far- Throws:
IOException
-
alignFilePointer
public final long alignFilePointer(int alignmentBytes) throws IOExceptionAligns the current file pointer to multiples ofalignmentBytesbytes to improve reads with mmap. This will write between 0 and(alignmentBytes-1)zero bytes usingDataOutput.writeByte(byte).- Parameters:
alignmentBytes- the alignment to which it should forward file pointer (must be a power of 2)- Returns:
- the new file pointer after alignment
- Throws:
IOException- See Also:
alignOffset(long, int)
-
alignOffset
public static final long alignOffset(long offset, int alignmentBytes)Aligns the givenoffsetto multiples ofalignmentBytesbytes by rounding up. The alignment must be a power of 2.
-
-