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Woodstox is a high-performance XML processor that
implements Stax (JSR-173) and SAX2 APIs
The newest version!
package com.ctc.wstx.io;
import java.io.*;
import com.ctc.wstx.api.ReaderConfig;
/**
* Simple basic class for optimized Readers Woodstox has; implements
* "cookie-cutter" methods that are used by all actual implementations.
*/
abstract class BaseReader
extends Reader
{
protected final static char NULL_CHAR = (char) 0;
protected final static char NULL_BYTE = (byte) 0;
/**
* In xml 1.1, NEL (0x85) behaves much the way \n does (can
* be follow \r as part of the linefeed
*/
protected final static char CONVERT_NEL_TO = '\n';
/**
* In xml 1.1, LSEP bit like \n, or \r. Need to choose one as the
* result. Let's use \n, for simplicity
*/
protected final static char CONVERT_LSEP_TO = '\n';
/**
* DEL character is both the last ascii char, and illegal in xml 1.1.
*/
final static char CHAR_DEL = (char) 127;
protected final ReaderConfig mConfig;
private InputStream mIn;
protected byte[] mByteBuffer;
/**
* Pointer to the next available byte (if any), iff less than
* mByteBufferEnd
*/
protected int mBytePtr;
/**
* Pointed to the end marker, that is, position one after the last
* valid available byte.
*/
protected int mByteBufferEnd;
/**
* Flag that indicates whether the read buffer is to be recycled
* when Reader is closed or not.
*/
private final boolean mRecycleBuffer;
/*
////////////////////////////////////////
// Life-cycle
////////////////////////////////////////
*/
protected BaseReader(ReaderConfig cfg, InputStream in, byte[] buf, int ptr, int len,
boolean recycleBuffer)
{
mConfig = cfg;
mIn = in;
mByteBuffer = buf;
mBytePtr = ptr;
mByteBufferEnd = len;
mRecycleBuffer = recycleBuffer;
}
/*
////////////////////////////////////////
// Configuration
////////////////////////////////////////
*/
/**
* Method that can be called to indicate the xml conformance used
* when reading content using this reader. Some of the character
* validity checks need to be done at reader level, and sometimes
* they depend on xml level (for example, xml 1.1 has new linefeeds
* and both more and less restricted characters).
*/
public abstract void setXmlCompliancy(int xmlVersion);
/**
* Method that can be used to see if we can actually modify the
* underlying buffer. This is the case if we are managing the buffer,
* but not if it was just given to us.
*/
protected final boolean canModifyBuffer()
{
return mRecycleBuffer;
}
/*
////////////////////////////////////////
// Reader API
////////////////////////////////////////
*/
public void close()
throws IOException
{
InputStream in = mIn;
if (in != null) {
mIn = null;
freeBuffers();
in.close();
}
}
char[] mTmpBuf = null;
/**
* Although this method is implemented by the base class, AND it should
* never be called by Woodstox code, let's still implement it bit more
* efficiently just in case
*/
public int read()
throws IOException
{
if (mTmpBuf == null) {
mTmpBuf = new char[1];
}
if (read(mTmpBuf, 0, 1) < 1) {
return -1;
}
return mTmpBuf[0];
}
/*
////////////////////////////////////////
// Internal/package methods:
////////////////////////////////////////
*/
protected final InputStream getStream() { return mIn; }
/**
* Method for reading as many bytes from the underlying stream as possible
* (that fit in the buffer), to the beginning of the buffer.
*/
protected final int readBytes()
throws IOException
{
mBytePtr = 0;
mByteBufferEnd = 0;
if (mIn != null) {
int count = mIn.read(mByteBuffer, 0, mByteBuffer.length);
if (count > 0) {
mByteBufferEnd = count;
}
return count;
}
return -1;
}
/**
* Method for reading as many bytes from the underlying stream as possible
* (that fit in the buffer considering offset), to the specified offset.
*
* @return Number of bytes read, if any; -1 to indicate none available
* (that is, end of input)
*/
protected final int readBytesAt(int offset)
throws IOException
{
// shouldn't modify mBytePtr, assumed to be 'offset'
if (mIn != null) {
int count = mIn.read(mByteBuffer, offset, mByteBuffer.length - offset);
if (count > 0) {
mByteBufferEnd += count;
}
return count;
}
return -1;
}
/**
* This method should be called along with (or instead of) normal
* close. After calling this method, no further reads should be tried.
* Method will try to recycle read buffers (if any).
*/
public final void freeBuffers()
{
/* 11-Apr-2005, TSa: Ok, we can release the buffer now, to be
* recycled by the next stream reader instantiated by this
* thread (if any).
*/
if (mRecycleBuffer) {
byte[] buf = mByteBuffer;
if (buf != null) {
mByteBuffer = null;
if (mConfig != null) {
mConfig.freeFullBBuffer(buf);
}
}
}
}
protected void reportBounds(char[] cbuf, int start, int len)
throws IOException
{
throw new ArrayIndexOutOfBoundsException("read(buf,"+start+","+len+"), cbuf["+cbuf.length+"]");
}
protected void reportStrangeStream()
throws IOException
{
throw new IOException("Strange I/O stream, returned 0 bytes on read");
}
protected void reportInvalidXml11(int value, int bytePos, int charPos)
throws IOException
{
throw new CharConversionException("Invalid character 0x"
+Integer.toHexString(value)
+", can only be included in xml 1.1 using character entities (at char #"+charPos+", byte #"+bytePos+")");
}
}