Module java.desktop
Package 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.

  • Field Summary

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

  • Constructor Summary

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

  • 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