javax.swing.text
class AbstractWriter

java.lang.Object javax.swing.text.AbstractWriter

Direct Known Subclasses:

HTMLWriter, MinimalHTMLWriter

public abstract class AbstractWriter
extends Object

AbstractWriter is an abstract class that actually does the work of writing out the element tree including the attributes. In terms of how much is written out per line, the writer defaults to 100. But this value can be set by subclasses.

NEWLINE

protected static final char NEWLINE

How the text packages models newlines.

AbstractWriter

protected AbstractWriter(Writer w,
                         Document doc)

Creates a new AbstractWriter. Initializes the ElementIterator with the default root of the document.

Parameters:

w - a Writer.

doc - a Document

AbstractWriter

protected AbstractWriter(Writer w,
                         Document doc,
                         int pos,
                         int len)

Creates a new AbstractWriter. Initializes the ElementIterator with the element passed in.

Parameters:

w - a Writer

doc - an Element

pos - The location in the document to fetch the content.

len - The amount to write out.

AbstractWriter

protected AbstractWriter(Writer w,
                         Element root)

Creates a new AbstractWriter. Initializes the ElementIterator with the element passed in.

Parameters:

w - a Writer

root - an Element

AbstractWriter

protected AbstractWriter(Writer w,
                         Element root,
                         int pos,
                         int len)

Creates a new AbstractWriter. Initializes the ElementIterator with the element passed in.

Parameters:

w - a Writer

root - an Element

pos - The location in the document to fetch the content.

len - The amount to write out.

decrIndent

protected void decrIndent()

Decrements the indent level.

getCanWrapLines

protected boolean getCanWrapLines()

Returns whether or not the lines can be wrapped. If this is false no lineSeparator's will be output.

getCurrentLineLength

protected int getCurrentLineLength()

Returns the current line length.

getDocument

protected Document getDocument()

Fetches the document.

Returns:

the Document.

getElementIterator

protected ElementIterator getElementIterator()

Fetches the ElementIterator.

Returns:

the ElementIterator.

getEndOffset

public int getEndOffset()

Returns the last offset to be output.

getIndentLevel

protected int getIndentLevel()

Returns the current indentation level. That is, the number of times incrIndent has been invoked minus the number of times decrIndent has been invoked.

getIndentSpace

protected int getIndentSpace()

Returns the amount of space to indent.

getLineLength

protected int getLineLength()

Returns the maximum line length.

getLineSeparator

public String getLineSeparator()

Returns the string used to represent newlines.

getStartOffset

public int getStartOffset()

Returns the first offset to be output.

getText

protected String getText(Element elem)
                  throws BadLocationException

Returns the text associated with the element. The assumption here is that the element is a leaf element. Throws a BadLocationException when encountered.

Parameters:

elem - an Element

Returns:

the text as a String

Throws:

BadLocationException - if pos represents an invalid location within the document

getWriter

protected Writer getWriter()

Returns the Writer that is used to output the content.

incrIndent

protected void incrIndent()

Increments the indent level. If indenting would cause getIndentSpace() *getIndentLevel() to be > than getLineLength() this will not cause an indent.

indent

protected void indent()
               throws IOException

Does indentation. The number of spaces written out is indent level times the space to map mapping. If the current line is empty, this will not make it so that the current line is still considered empty.

Throws:

IOException - on any I/O error

inRange

protected boolean inRange(Element next)

This method determines whether the current element is in the range specified. When no range is specified, the range is initialized to be the entire document. inRange() returns true if the range specified intersects with the element's range.

Parameters:

next - an Element.

Returns:

boolean that indicates whether the element is in the range.

isLineEmpty

protected boolean isLineEmpty()

Returns true if the current line should be considered empty. This is true when getCurrentLineLength == 0 || indent has been invoked on an empty line.

output

protected void output(char[] content,
                      int start,
                      int length)
               throws IOException

The last stop in writing out content. All the write methods eventually make it to this method, which invokes write on the Writer.

This method also updates the line length based on length. If this is invoked to output a newline, the current line length will need to be reset as will no longer be valid. If it is up to the caller to do this. Use writeLineSeparator to write out a newline, which will property update the current line length.

Parameters:

content

start

length

Throws:

IOException

setCanWrapLines

protected void setCanWrapLines(boolean newValue)

Sets whether or not lines can be wrapped. This can be toggled during the writing of lines. For example, outputting HTML might set this to false when outputting a quoted string.

Parameters:

newValue

setCurrentLineLength

protected void setCurrentLineLength(int length)

Sets the current line length.

Parameters:

length

setIndentSpace

protected void setIndentSpace(int space)

Enables subclasses to specify how many spaces an indent maps to. When indentation takes place, the indent level is multiplied by this mapping. The default is 2.

Parameters:

space - an int representing the space to indent mapping.

setLineLength

protected void setLineLength(int l)

Enables subclasses to set the number of characters they want written per line. The default is 100.

Parameters:

l - the maximum line length.

setLineSeparator

public void setLineSeparator(String value)

Sets the String used to reprsent newlines. This is initialized in the constructor from either the Document, or the System property line.separator.

Parameters:

value

text

protected void text(Element elem)
             throws BadLocationException,
                    IOException

Writes out text. If a range is specified when the constructor is invoked, then only the appropriate range of text is written out.

Parameters:

elem - an Element.

Throws:

BadLocationException - if pos represents an invalid location within the document.

IOException - on any I/O error

write

protected abstract void write()
                       throws IOException,
                              BadLocationException

This abstract method needs to be implemented by subclasses. Its responsibility is to iterate over the elements and use the write() methods to generate output in the desired format.

Throws:

IOException

BadLocationException

write

protected void write(char ch)
              throws IOException

Writes out a character. This is implemented to invoke the write method that takes a char[].

Parameters:

ch - a char.

Throws:

IOException - on any I/O error

write

protected void write(char[] chars,
                     int startIndex,
                     int length)
              throws IOException

All write methods call into this one. If getCanWrapLines() returns false, this will call output with each sequence of chars that doesn't contain a NEWLINE, followed by a call to writeLineSeparator. On the other hand, if getCanWrapLines() returns true, this will split the string, as necessary, so getLineLength is honored. The only exception is if the current string contains no whitespace, and won't fit in which case the line length will exceed getLineLength.

Parameters:

chars

startIndex

length

Throws:

IOException

write

protected void write(String content)
              throws IOException

Writes out a string. This is implemented to invoke the write method that takes a char[].

Parameters:

content - a String.

Throws:

IOException - on any I/O error

writeAttributes

protected void writeAttributes(AttributeSet attr)
                        throws IOException

Writes out the set of attributes as " =" pairs. It throws an IOException when encountered.

Parameters:

attr - an AttributeSet.

Throws:

IOException - on any I/O error

writeLineSeparator

protected void writeLineSeparator()
                           throws IOException

Writes the line separator. This invokes output directly as well as setting the lineLength to 0.

Throws:

IOException