org.apache.lucene.store

Class IndexInput

java.lang.Object

org.apache.lucene.store.DataInput

org.apache.lucene.store.IndexInput

All Implemented Interfaces:

Closeable, Cloneable

Direct Known Subclasses:

BufferedIndexInput, ChecksumIndexInput, RAMInputStream

public abstract class IndexInput
extends DataInput
implements Cloneable, Closeable

Abstract base class for input from a file in a Directory. A random-access input stream. Used for all Lucene index input operations.

See Also:

Directory

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	IndexInput() Deprecated. please pass resourceDescription
protected	IndexInput(String resourceDescription) resourceDescription should be a non-null, opaque string describing this resource; it's returned from toString().

Method Summary

Methods

Modifier and Type	Method and Description
abstract void	close() Closes the stream to further operations.
void	copyBytes(IndexOutput out, long numBytes) Copies numBytes bytes to the given IndexOutput.
abstract long	getFilePointer() Returns the current position in this file, where the next read will occur.
abstract long	length() The number of bytes in the file.
abstract void	seek(long pos) Sets current position in this file, where the next read will occur.
void	skipChars(int length) Deprecated. this method operates on old "modified utf8" encoded strings
String	toString()

Methods inherited from class org.apache.lucene.store.DataInput

clone, readByte, readBytes, readBytes, readChars, readInt, readLong, readShort, readString, readStringStringMap, readVInt, readVLong, setModifiedUTF8StringsMode

Methods inherited from class java.lang.Object

equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Constructor Detail

IndexInput

@Deprecated
protected IndexInput()

Deprecated. please pass resourceDescription

IndexInput

protected IndexInput(String resourceDescription)

resourceDescription should be a non-null, opaque string describing this resource; it's returned from toString().

Method Detail

skipChars

@Deprecated
public void skipChars(int length)
               throws IOException

Deprecated. this method operates on old "modified utf8" encoded strings

Expert Similar to DataInput.readChars(char[], int, int) but does not do any conversion operations on the bytes it is reading in. It still has to invoke DataInput.readByte() just as DataInput.readChars(char[], int, int) does, but it does not need a buffer to store anything and it does not have to do any of the bitwise operations, since we don't actually care what is in the byte except to determine how many more bytes to read

Parameters:

length - The number of chars to read

Throws:

IOException

close

public abstract void close()
                    throws IOException

Closes the stream to further operations.

Specified by:

close in interface Closeable

Throws:

IOException

getFilePointer

public abstract long getFilePointer()

Returns the current position in this file, where the next read will occur.

See Also:

seek(long)

seek

public abstract void seek(long pos)
                   throws IOException

Sets current position in this file, where the next read will occur.

Throws:

IOException

See Also:

getFilePointer()

length

public abstract long length()

The number of bytes in the file.

copyBytes

public void copyBytes(IndexOutput out,
             long numBytes)
               throws IOException

Copies numBytes bytes to the given IndexOutput.

NOTE: this method uses an intermediate buffer to copy the bytes. Consider overriding it in your implementation, if you can make a better, optimized copy.

NOTE ensure that there are enough bytes in the input to copy to output. Otherwise, different exceptions may be thrown, depending on the implementation.

Throws:

IOException

toString

public String toString()

Overrides:

toString in class Object