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.

Field Summary

Modifier and Type Field Description
protected static final char NEWLINE
How the text packages models newlines.

Constructor Summary

AbstractWriter(Writer w, Document doc)
AbstractWriter(Writer w, Document doc, int pos, int len)
AbstractWriter(Writer w, Element root)
AbstractWriter(Writer w, Element root, int pos, int len)
Modifier Constructor Description
protected
Creates a new AbstractWriter.
protected
Creates a new AbstractWriter.
protected
Creates a new AbstractWriter.
protected
Creates a new AbstractWriter.

Method Summary

Modifier and Type Method Description
protected void decrIndent()
Decrements the indent level.
protected boolean getCanWrapLines()
Returns whether or not the lines can be wrapped.
protected int getCurrentLineLength()
Returns the current line length.
protected Document getDocument()
Fetches the document.
protected ElementIterator getElementIterator()
Fetches the ElementIterator.
int getEndOffset()
Returns the last offset to be output.
protected int getIndentLevel()
Returns the current indentation level.
protected int getIndentSpace()
Returns the amount of space to indent.
protected int getLineLength()
Returns the maximum line length.
String getLineSeparator()
Returns the string used to represent newlines.
int getStartOffset()
Returns the first offset to be output.
protected String getText(Element elem)
Returns the text associated with the element.
protected Writer getWriter()
Returns the Writer that is used to output the content.
protected void incrIndent()
Increments the indent level.
protected void indent()
Does indentation.
protected boolean inRange(Element next)
This method determines whether the current element is in the range specified.
protected boolean isLineEmpty()
Returns true if the current line should be considered empty.
protected void output(char[] content, int start, int length)
The last stop in writing out content.
protected void setCanWrapLines(boolean newValue)
Sets whether or not lines can be wrapped.
protected void setCurrentLineLength(int length)
Sets the current line length.
protected void setIndentSpace(int space)
Enables subclasses to specify how many spaces an indent maps to.
protected void setLineLength(int l)
Enables subclasses to set the number of characters they want written per line.
void setLineSeparator(String value)
Sets the String used to represent newlines.
protected void text(Element elem)
Writes out text.
protected abstract void write()
This abstract method needs to be implemented by subclasses.
protected void write(char ch)
Writes out a character.
protected void write(char[] chars, int startIndex, int length)
All write methods call into this one.
protected void write(String content)
Writes out a string.
protected void writeAttributes(AttributeSet attr)
Writes out the set of attributes as " <name>=<value>" pairs.
protected void writeLineSeparator()
Writes the line separator.

Methods declared in class java.lang.Object

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

Field Details

NEWLINE

protected static final char NEWLINE
How the text packages models newlines.
See Also:

Constructor Details

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.

Method Details

getStartOffset

public int getStartOffset()
Returns the first offset to be output.
Returns:
the first offset to be output
Since:
1.3

getEndOffset

public int getEndOffset()
Returns the last offset to be output.
Returns:
the last offset to be output
Since:
1.3

getElementIterator

protected ElementIterator getElementIterator()
Fetches the ElementIterator.
Returns:
the ElementIterator.

getWriter

protected Writer getWriter()
Returns the Writer that is used to output the content.
Returns:
the Writer that is used to output the content
Since:
1.3

getDocument

protected Document getDocument()
Fetches the document.
Returns:
the Document.

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.

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 - if an I/O problem has occurred
BadLocationException - for an invalid location within the document

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

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:
IOException - on any I/O error
BadLocationException - if pos represents an invalid location within the document.

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.

getLineLength

protected int getLineLength()
Returns the maximum line length.
Returns:
the maximum line length
Since:
1.3

setCurrentLineLength

protected void setCurrentLineLength(int length)
Sets the current line length.
Parameters:
length - the new line length
Since:
1.3

getCurrentLineLength

protected int getCurrentLineLength()
Returns the current line length.
Returns:
the current line length
Since:
1.3

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.
Returns:
true if the current line should be considered empty
Since:
1.3

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 - new value for line wrapping
Since:
1.3

getCanWrapLines

protected boolean getCanWrapLines()
Returns whether or not the lines can be wrapped. If this is false no lineSeparator's will be output.
Returns:
whether or not the lines can be wrapped
Since:
1.3

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.

getIndentSpace

protected int getIndentSpace()
Returns the amount of space to indent.
Returns:
the amount of space to indent
Since:
1.3

setLineSeparator

public void setLineSeparator(String value)
Sets the String used to represent newlines. This is initialized in the constructor from either the Document, or the System property line.separator.
Parameters:
value - the new line separator
Since:
1.3

getLineSeparator

public String getLineSeparator()
Returns the string used to represent newlines.
Returns:
the string used to represent newlines
Since:
1.3

incrIndent

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

decrIndent

protected void decrIndent()
Decrements the indent level.

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.
Returns:
the current indentation level
Since:
1.3

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

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(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

writeLineSeparator

protected void writeLineSeparator() throws IOException
Writes the line separator. This invokes output directly as well as setting the lineLength to 0.
Throws:
IOException - on any I/O error
Since:
1.3

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 - characters to output
startIndex - starting index
length - length of output
Throws:
IOException - on any I/O error
Since:
1.3

writeAttributes

protected void writeAttributes(AttributeSet attr) throws IOException
Writes out the set of attributes as " <name>=<value>" pairs. It throws an IOException when encountered.
Parameters:
attr - an AttributeSet.
Throws:
IOException - on any I/O error

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 - characters to output
start - starting index
length - length of output
Throws:
IOException - on any I/O error
Since:
1.3

© 1993, 2021, Oracle and/or its affiliates. All rights reserved.
Documentation extracted from Debian's OpenJDK Development Kit package.
Licensed under the GNU General Public License, version 2, with the Classpath Exception.
Various third party code in OpenJDK is licensed under different licenses (see Debian package).
Java and OpenJDK are trademarks or registered trademarks of Oracle and/or its affiliates.
https://docs.oracle.com/en/java/javase/17/docs/api/java.desktop/javax/swing/text/AbstractWriter.html