Module org.apache.sis.util
Package org.apache.sis.io

Class TableAppender

Object
TableAppender
All Implemented Interfaces:
Flushable, Appendable
public class TableAppender extends Object implements Flushable
An Appendable which formats the text as a table suitable for displaying in devices using a monospaced font. Columns are separated by tabulations ('\t') and rows are separated by line or paragraph separators. The content of every table cells are stored in memory until the flush() method is invoked. When invoked, flush() copies the cell contents to the underlying stream or buffer while replacing tabulations by some amount of spaces and drawing borders. The exact number of spaces is computed from the cell widths.

For example, the following code:

TableAppender table = new TableAppender(System.out);
table.nextLine('═');
table.append("English\tFrench\tr.e.d.\n");
table.nextLine('-');
table.append("Mercury\tMercure\t0.382\n")
     .append("Venus\tVénus\t0.949\n")
     .append("Earth\tTerre\t1.00\n")
     .append("Mars\tMars\t0.532\n");
table.nextLine('═');
table.flush();
produces the following output: 
   ╔═════════╤═════════╤════════╗
   ║ English │ French  │ r.e.d. ║
   ╟─────────┼─────────┼────────╢
   ║ Mercury │ Mercure │ 0.382  ║
   ║ Venus   │ Vénus   │ 0.949  ║
   ║ Earth   │ Terre   │ 1.00   ║
   ║ Mars    │ Mars    │ 0.532  ║
   ╚═════════╧═════════╧════════╝
Since:
0.3
See Also:

  • Field Details

    • ALIGN_LEFT

      public static final byte ALIGN_LEFT
      A possible value for cell alignment. This specifies that the text is aligned to the left indent and extra whitespace should be placed on the right.
      See Also:

    • ALIGN_CENTER

      public static final byte ALIGN_CENTER
      A possible value for cell alignment. This specifies that the text is aligned to the center and extra whitespace should be placed equally on the left and right.
      See Also:

    • ALIGN_RIGHT

      public static final byte ALIGN_RIGHT
      A possible value for cell alignment. This specifies that the text is aligned to the right indent and extra whitespace should be placed on the left.
      See Also:

    • out

      protected final Appendable out
      The underlying character output stream or buffer.

  • Constructor Details

    • TableAppender

      public TableAppender()
      Creates a new table formatter writing in an internal buffer with a default column separator. The default is a vertical double line for the left and right table borders, and a single line between the columns.

    • TableAppender

      public TableAppender(String separator)
      Creates a new table formatter writing in an internal buffer with the specified column separator.
      Parameters:
      separator - string to write between columns.

    • TableAppender

      public TableAppender(Appendable out)
      Creates a new table formatter writing in the given output with a default column separator. The default is a vertical double line for the left and right table borders, and a single line between the columns.
      Parameters:
      out - the underlying stream or buffer to write to.

    • TableAppender

      public TableAppender(Appendable out, String separator)
      Creates a new table formatter writing in the given output with the specified column separator.
      Parameters:
      out - the underlying stream or buffer to write to.
      separator - string to write between columns.

    • TableAppender

      public TableAppender(Appendable out, String leftBorder, String separator, String rightBorder)
      Creates a new table formatter writing in the given output with the specified column separator and border.
      Parameters:
      out - the underlying stream or buffer to write to.
      left­Border - string to write on the left side of the table.
      separator - string to write between columns.
      right­Border - string to write on the right side of the table.
      Since:
      0.8

  • Method Details

    • isMultiLinesCells

      public boolean isMultiLinesCells()
      Returns true if EOL characters are used for line feeds inside current cells.
      Returns:
      true if EOL characters are to be write inside the cell.

    • setMultiLinesCells

      public void setMultiLinesCells(boolean multiLines)
      Sets the desired behavior for EOL and tabulations characters.
      • If true, then tabulations, line and paragraph separator characters are copied into the current cell. Subsequent writing operations will continue inside the same cell.
      • If false, then tabulations move to next column and EOL move to the first cell of next row (i.e. tabulation and EOL are equivalent to next­Column() and next­Line() calls respectively).
      The default value is false.
      Parameters:
      multi­Lines - true true if EOL are used for line feeds inside current cells, or false if EOL move to the next row.

    • getCellAlignment

      public byte getCellAlignment()
      Returns the alignment of the text inside the current cell. The default value is ALIGN_LEFT.
      Returns:
      current cell alignment as one of the ALIGN_LEFT, ALIGN_RIGHT or ALIGN_CENTER constants.

    • setCellAlignment

      public void setCellAlignment(byte alignment)
      Sets the alignment of the text inside the current cell. The alignments of any cell written prior this method call are left unchanged. The new alignment will apply to the next cells too until this set­Cell­Alignment(…) method is invoked again with a different value.

      If this method is never invoked, then the default alignment is ALIGN_LEFT.

      Parameters:
      alignment - the new cell alignment as one of the ALIGN_LEFT, ALIGN_RIGHT or ALIGN_CENTER constants.

    • getLineSeparator

      public String getLineSeparator()
      Returns the line separator between table rows. This is the first line separator found in the text formatted as a table, or the system default if no line separator was found in the text to format.
      Returns:
      the line separator between table rows.
      Since:
      1.0

    • getRowCount

      public int getRowCount()
      Returns the number of rows in this table. This count is reset to 0 by flush().
      Returns:
      the number of rows in this table.

    • getColumnCount

      public int getColumnCount()
      Returns the number of columns in this table.
      Returns:
      the number of columns in this table.

    • append

      public TableAppender append(char c)
      Writes a single character. If is­Multi­Lines­Cells() is false (which is the default), then:
      Specified by:
      append in interface Appendable
      Parameters:
      c - character to write.
      Returns:
      this.

    • append

      public TableAppender append(CharSequence sequence)
      Appends the specified character sequence.
      Specified by:
      append in interface Appendable
      Parameters:
      sequence - the character sequence to append, or null.
      Returns:
      a reference to this Appendable.

    • append

      public TableAppender append(CharSequence sequence, int start, int end)
      Writes a portion of a character sequence. Tabulations and line separators are interpreted as by append(char).
      Specified by:
      append in interface Appendable
      Parameters:
      sequence - the character sequence to be written.
      start - index from which to start reading characters.
      end - index of the character following the last character to read.
      Returns:
      this.

    • appendHorizontalSeparator

      public void appendHorizontalSeparator()
      Writes an horizontal separator using the '─' character.
      See Also:

    • nextColumn

      public void nextColumn()
      Moves one column to the right. The subsequent writing operations will occur in a new cell on the same row.

    • nextColumn

      public void nextColumn(char fill)
      Moves one column to the right, filling remaining space with the given character. The subsequent writing operations will occur in a new cell on the same row.

      Calling next­Column('*') from the first character in a cell is a convenient way to put a pad value in this cell.

      Parameters:
      fill - character filling the cell (default to whitespace).

    • nextLine

      public void nextLine()
      Moves to the first column on the next row. The subsequent writing operations will occur on a new row.

    • nextLine

      public void nextLine(char fill)
      Moves to the first column on the next row, filling every remaining cell in the current row with the specified character. The subsequent writing operations will occur on a new row.

      Calling next­Line('-') or next­Line('═') from the first column of a row is a convenient way to fill this row with a line separator.

      Parameters:
      fill - character filling the rest of the line (default to whitespace). This character may be use as a row separator.
      See Also:

    • flush

      public void flush() throws IOException
      Flushes the table content to the underlying stream or buffer. This method should not be called before the table is completed (otherwise, columns may have the wrong width).
      Specified by:
      flush in interface Flushable
      Throws:
      IOException - if an output operation failed.

    • toString

      public String toString()
      Returns the content of this Table­Appender as a string if possible.
      • If this Table­Appender has been created without explicit Appendable, then this method always returns the current table content formatted as a string.
      • Otherwise, if out implements Char­Sequence or is directly or indirectly a wrapper around a Char­Sequence, returns its to­String() representation. The string will contain this table content only if flush() has been invoked prior this to­String() method.
      • Otherwise returns the localized "Unavailable content" string.
      Returns:
      the content of this Appendable, or a localized message for unavailable content.
      See Also: