jxl.write.biff.SSTContinueRecord Maven / Gradle / Ivy
Go to download
Show more of this group Show more artifacts with this name
Show all versions of jxl Show documentation
Show all versions of jxl Show documentation
JExcelApi is a java library which provides the ability to read, write, and modify Microsoft Excel spreadsheets.
The newest version!
/*********************************************************************
*
* Copyright (C) 2002 Andrew Khan
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
***************************************************************************/
package jxl.write.biff;
import java.util.ArrayList;
import java.util.Iterator;
import jxl.biff.IntegerHelper;
import jxl.biff.StringHelper;
import jxl.biff.Type;
import jxl.biff.WritableRecordData;
/**
* A continuation of a shared string table record.
*/
class SSTContinueRecord extends WritableRecordData
{
/**
* The first string is a special case
*/
private String firstString;
/**
* Indicates whether or not we need to include the length information
* for the first string
*/
private boolean includeLength;
/**
* The length of the first string
*/
private int firstStringLength;
/**
* The list of strings
*/
private ArrayList strings;
/**
* The list of string lengths
*/
private ArrayList stringLengths;
/**
* The binary data
*/
private byte[] data;
/**
* The count of bytes needed so far to contain this record
*/
private int byteCount;
/**
* The maximum amount of bytes available for the SST record
*/
private static int maxBytes = 8228 - // max length
4; // standard biff record stuff
/**
* Constructor
*
* @param numRefs the number of string references in the workbook
* @param s the number of strings
*/
public SSTContinueRecord()
{
super(Type.CONTINUE);
byteCount = 0;
strings = new ArrayList(50);
stringLengths = new ArrayList(50);
}
/**
* Adds the first string to this SST record
*
* @param s the string to add
* @param b include the length information for the first string
* @return the number of characters not added
*/
public int setFirstString(String s, boolean b)
{
includeLength = b;
firstStringLength = s.length();
int bytes = 0;
if (!includeLength)
{
bytes = s.length() * 2 + 1;
}
else
{
bytes = s.length() * 2 + 3;
}
if (bytes <= maxBytes)
{
firstString = s;
byteCount += bytes;
return 0;
}
// Calculate the number of characters we can add
// The bytes variable will always be an odd number
int charsAvailable = includeLength ? (maxBytes - 4) / 2 :
(maxBytes - 2) / 2;
// Add what part of the string we can
firstString = s.substring(0, charsAvailable);
byteCount = maxBytes - 1;
return s.length() - charsAvailable;
}
/**
* Gets the current offset into this record, excluding the header fields
*
* @return the number of bytes after the header field
*/
public int getOffset()
{
return byteCount;
}
/**
* Adds a string to this record. It returns the number of string
* characters not added, due to space constraints. In the event
* of this being non-zero, a continue record will be needed
*
* @param s the string to add
* @return the number of characters not added
*/
public int add(String s)
{
int bytes = s.length() * 2 + 3;
// Must be able to add at least the first character of the string
// onto the SST
if (byteCount >= maxBytes - 5)
{
return s.length();
}
stringLengths.add(new Integer(s.length()));
if (bytes + byteCount < maxBytes)
{
// add the string and return
strings.add(s);
byteCount += bytes;
return 0;
}
// Calculate the number of characters we can add
int bytesLeft = maxBytes - 3 - byteCount;
int charsAvailable = bytesLeft % 2 == 0 ? bytesLeft / 2 :
(bytesLeft - 1) / 2;
// Add what part of the string we can
strings.add(s.substring(0, charsAvailable));
byteCount += charsAvailable * 2 + 3;
return s.length() - charsAvailable;
}
/**
* Gets the binary data for output to file
*
* @return the binary data
*/
public byte[] getData()
{
data = new byte[byteCount];
int pos = 0;
// Write out the first string
if (includeLength)
{
IntegerHelper.getTwoBytes(firstStringLength, data, 0);
data[2] = 0x01;
pos = 3;
}
else
{
// Just include the unicode indicator
data[0] = 0x01;
pos = 1;
}
StringHelper.getUnicodeBytes(firstString, data, pos);
pos += firstString.length() * 2;
// Now write out the remainder of the strings
Iterator i = strings.iterator();
String s = null;
int length = 0;
int count = 0;
while (i.hasNext())
{
s = (String) i.next();
length = ( (Integer) stringLengths.get(count)).intValue();
IntegerHelper.getTwoBytes(length, data, pos);
data[pos+2] = 0x01;
StringHelper.getUnicodeBytes(s, data, pos+3);
pos += s.length() * 2 + 3;
count++;
}
return data;
}
}