Writer class for documents.
*
* DocWriter is the abstract class of several writers such
* as PdfWriter and HtmlWriter.
* A DocWriter can be added as a DocListener
* to a certain Document by getting an instance (see method
* getInstance() in the specific writer-classes).
* Every Element added to the original Document
* will be written to the OutputStream of the listening
* DocWriter.
*
* @see Document
* @see DocListener
*/
public abstract class DocWriter implements DocListener {
/** This is some byte that is often used. */
public static final byte NEWLINE = (byte)'\n';
/** This is some byte that is often used. */
public static final byte TAB = (byte)'\t';
/** This is some byte that is often used. */
public static final byte LT = (byte)'<';
/** This is some byte that is often used. */
public static final byte SPACE = (byte)' ';
/** This is some byte that is often used. */
public static final byte EQUALS = (byte)'=';
/** This is some byte that is often used. */
public static final byte QUOTE = (byte)'\"';
/** This is some byte that is often used. */
public static final byte GT = (byte)'>';
/** This is some byte that is often used. */
public static final byte FORWARD = (byte)'/';
// membervariables
/** The pageSize. */
protected Rectangle pageSize;
/** This is the document that has to be written. */
protected Document document;
/** The outputstream of this writer. */
protected OutputStreamCounter os;
/** Is the writer open for writing? */
protected boolean open = false;
/** Do we have to pause all writing actions? */
protected boolean pause = false;
/** Closes the stream on document close */
protected boolean closeStream = true;
// constructor
protected DocWriter() {
}
/**
* Constructs a DocWriter.
*
* @param document The Document that has to be written
* @param os The OutputStream the writer has to write to.
*/
protected DocWriter(Document document, OutputStream os) {
this.document = document;
this.os = new OutputStreamCounter(new BufferedOutputStream(os));
}
// implementation of the DocListener methods
/**
* Signals that an Element was added to the Document.
*
* This method should be overriden in the specific
* This method should be overriden in the specific
* This does nothing. Has to be overridden if needed.
*
* @param marginLeft the margin on the left
* @param marginRight the margin on the right
* @param marginTop the margin on the top
* @param marginBottom the margin on the bottom
* @return
* This does nothing. Has to be overridden if needed.
*
* @return
* This method should be overriden in the specific
* This method should be overriden in the specific
* This method should be overriden in the specific
* This method should be overriden in the specific
* This method should be overriden in the specific
* This method should be overriden in the specific DocWriter classes
* derived from this abstract class.
*
* @param element A high level object to add
* @return false
* @throws DocumentException when a document isn't open yet, or has been closed
*/
public boolean add(Element element) throws DocumentException {
return false;
}
/**
* Signals that the Document was opened.
*/
public void open() {
open = true;
}
/**
* Sets the pagesize.
*
* @param pageSize the new pagesize
* @return a boolean
*/
public boolean setPageSize(Rectangle pageSize) {
this.pageSize = pageSize;
return true;
}
/**
* Sets the Watermark.
* DocWriter classes
* derived from this abstract class if they actually support the use of
* a Watermark.
*
* @param watermark A watermark object
* @return false (because watermarks aren't supported by default).
*/
public boolean add(Watermark watermark) {
return false;
}
/**
* Removes the Watermark (if there is one).
*/
public void removeWatermark() {
}
/**
* Sets the margins.
* false
*/
public boolean setMargins(float marginLeft, float marginRight, float marginTop, float marginBottom) {
return false;
}
/**
* Signals that an new page has to be started.
* true if the page was added, false if not.
* @throws DocumentException when a document isn't open yet, or has been closed
*/
public boolean newPage() throws DocumentException {
if (!open) {
return false;
}
return true;
}
/**
* Changes the header of this document.
* DocWriter classes
* derived from this abstract class if they actually support the use of
* headers.
*
* @param header the new header
*/
public void setHeader(HeaderFooter header) {
}
/**
* Resets the header of this document.
* DocWriter classes
* derived from this abstract class if they actually support the use of
* headers.
*/
public void resetHeader() {
}
/**
* Changes the footer of this document.
* DocWriter classes
* derived from this abstract class if they actually support the use of
* footers.
*
* @param footer the new footer
*/
public void setFooter(HeaderFooter footer) {
}
/**
* Resets the footer of this document.
* DocWriter classes
* derived from this abstract class if they actually support the use of
* footers.
*/
public void resetFooter() {
}
/**
* Sets the page number to 0.
* DocWriter classes
* derived from this abstract class if they actually support the use of
* pagenumbers.
*/
public void resetPageCount() {
}
/**
* Sets the page number.
* DocWriter classes
* derived from this abstract class if they actually support the use of
* pagenumbers.
*
* @param pageN the new page number
*/
public void setPageCount(int pageN) {
}
/**
* Signals that the Document was closed and that no other
* Elements will be added.
*/
public void close() {
open = false;
try {
os.flush();
if (closeStream)
os.close();
}
catch(IOException ioe) {
throw new ExceptionConverter(ioe);
}
}
// methods
/** Converts a String into a Byte array
* according to the ISO-8859-1 codepage.
* @param text the text to be converted
* @return the conversion result
*/
public static final byte[] getISOBytes(String text)
{
if (text == null)
return null;
int len = text.length();
byte b[] = new byte[len];
for (int k = 0; k < len; ++k)
b[k] = (byte)text.charAt(k);
return b;
}
/**
* Let the writer know that all writing has to be paused.
*/
public void pause() {
pause = true;
}
/**
* Let the writer know that writing may be resumed.
*/
public void resume() {
pause = false;
}
/**
* Flushes the BufferedOutputStream.
*/
public void flush() {
try {
os.flush();
}
catch(IOException ioe) {
throw new ExceptionConverter(ioe);
}
}
/**
* Writes a String to the OutputStream.
*
* @param string the String to write
* @throws IOException
*/
protected void write(String string) throws IOException {
os.write(getISOBytes(string));
}
/**
* Writes a number of tabs.
*
* @param indent the number of tabs to add
* @throws IOException
*/
protected void addTabs(int indent) throws IOException {
os.write(NEWLINE);
for (int i = 0; i < indent; i++) {
os.write(TAB);
}
}
/**
* Writes a key-value pair to the outputstream.
*
* @param key the name of an attribute
* @param value the value of an attribute
* @throws IOException
*/
protected void write(String key, String value)
throws IOException {
os.write(SPACE);
write(key);
os.write(EQUALS);
os.write(QUOTE);
write(value);
os.write(QUOTE);
}
/**
* Writes a starttag to the outputstream.
*
* @param tag the name of the tag
* @throws IOException
*/
protected void writeStart(String tag)
throws IOException {
os.write(LT);
write(tag);
}
/**
* Writes an endtag to the outputstream.
*
* @param tag the name of the tag
* @throws IOException
*/
protected void writeEnd(String tag)
throws IOException {
os.write(LT);
os.write(FORWARD);
write(tag);
os.write(GT);
}
/**
* Writes an endtag to the outputstream.
* @throws IOException
*/
protected void writeEnd()
throws IOException {
os.write(SPACE);
os.write(FORWARD);
os.write(GT);
}
/**
* Writes the markup attributes of the specified MarkupAttributes
* object to the OutputStream.
* @param mAtt the MarkupAttributes to write.
* @return true, if writing the markup attributes succeeded
* @throws IOException
*/
protected boolean writeMarkupAttributes(MarkupAttributes mAtt)
throws IOException
{
Iterator attributeIterator = mAtt.getMarkupAttributeNames().iterator();
boolean result = attributeIterator.hasNext();
while (attributeIterator.hasNext()) {
String name = String.valueOf(attributeIterator.next());
write(name, mAtt.getMarkupAttribute(name));
}
return result;
}
/**
* Returns true if the specified Element implements
* MarkupAttributes and has one or more attributes to write.
* @param element the Element to check.
* @return boolean.
*/
protected static boolean hasMarkupAttributes(Element element) {
return (element instanceof MarkupAttributes &&
!(((MarkupAttributes)element).getMarkupAttributeNames().isEmpty()));
}
/** Checks if the stream is to be closed on document close
* @return true if the stream is closed on documnt close
*
*/
public boolean isCloseStream() {
return closeStream;
}
/** Sets the close state of the stream after document close
* @param closeStream true if the stream is closed on document close
*
*/
public void setCloseStream(boolean closeStream) {
this.closeStream = closeStream;
}
/**
* @see com.lowagie.text.DocListener#clearTextWrap()
*/
public void clearTextWrap() throws DocumentException {
// do nothing
}
/**
* @see com.lowagie.text.DocListener#setMarginMirroring(boolean)
*/
public boolean setMarginMirroring(boolean MarginMirroring) {
return false;
}
}