Package org.apache.sis.io
Class TableAppender
java.lang.Object
org.apache.sis.io.Appender
org.apache.sis.io.TableAppender
- All Implemented Interfaces:
Flushable
,Appendable
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:
produces the following output:- Since:
- 0.3
- Version:
- 1.0
- See Also:
-
Nested Class Summary
Nested ClassesModifier and TypeClassDescriptionprivate static final class
A class wrapping a cell content and its text alignment. -
Field Summary
FieldsModifier and TypeFieldDescriptionstatic final byte
A possible value for cell alignment.static final byte
A possible value for cell alignment.static final byte
A possible value for cell alignment.private byte
Alignment for current and next cells.private static final char[][]
Drawing-box characters.private final StringBuilder
Temporary string buffer.private final List<TableAppender.Cell>
List ofTableAppender.Cell
objects, from left to right and top to bottom.private final String
The column separator, or an empty string if none.private int
Column position of the cell currently being written.private int
Line position of the cell currently being written.private final String
The left table border, or an empty string if none.private String
The line separator.private int[]
Maximum width for each columns.private boolean
Tells if cells can span more than one line.private boolean
Sets totrue
at construction time ifAppender.out
has been created by the constructor rather than supplied by the user.private final String
The right table border, or an empty string if none.private boolean
true
if the next character needs to be skipped if equals to'\n'
.private static final char
The character for empty spaces to insert between columns. -
Constructor Summary
ConstructorsConstructorDescriptionCreates a new table formatter writing in an internal buffer with a default column separator.TableAppender
(Appendable out) Creates a new table formatter writing in the given output with a default column separator.TableAppender
(Appendable out, String separator) Creates a new table formatter writing in the given output with the specified column separator.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.TableAppender
(String separator) Creates a new table formatter writing in an internal buffer with the specified column separator. -
Method Summary
Modifier and TypeMethodDescriptionappend
(char c) Writes a single character.append
(CharSequence sequence) Appends the specified character sequence.append
(CharSequence sequence, int start, int end) Writes a portion of a character sequence.void
Writes an horizontal separator using the'─'
character.void
flush()
Flushes the table content to the underlying stream or buffer.byte
Returns the alignment of the text inside the current cell.int
Returns the number of columns in this table.Returns the line separator between table rows.int
Returns the number of rows in this table.private static boolean
Checks ifarray
contains onlynull
elements.boolean
Returnstrue
if EOL characters are used for line feeds inside current cells.void
Moves one column to the right.void
nextColumn
(char fill) Moves one column to the right, filling remaining space with the given character.void
nextLine()
Moves to the first column on the next row.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.private static void
repeat
(Appendable out, char car, int count) Repeats a character.void
setCellAlignment
(byte alignment) Sets the alignment of the text inside the current cell.void
setMultiLinesCells
(boolean multiLines) Sets the desired behavior for EOL and tabulations characters.toString()
Returns the content of thisTableAppender
as a string if possible.private void
writeBorder
(int horizontalBorder, int verticalBorder, char horizontalChar) Writes a border or a corner to the underlying stream or buffer.private void
Writes the table without clearing theTableAppender
content.Methods inherited from class org.apache.sis.io.Appender
appendCodePoint, appendSurrogate, isHighSurrogate, lineSeparator, toCodePoint
-
Field Details
-
ALIGN_LEFT
public static final byte ALIGN_LEFTA 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_CENTERA 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_RIGHTA 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:
-
BOX
private static final char[][] BOXDrawing-box characters. The last two characters are horizontal and vertical line respectively. -
SPACE
private static final char SPACEThe character for empty spaces to insert between columns.- See Also:
-
buffer
Temporary string buffer. This buffer contains only one cell content. -
cells
List ofTableAppender.Cell
objects, from left to right and top to bottom. By convention, anull
value or aTableAppender.Cell
object withTableAppender.Cell.text == null
means that we need to move to the next line. -
alignment
private byte alignmentAlignment for current and next cells.- See Also:
-
currentColumn
private int currentColumnColumn position of the cell currently being written. The field is incremented every timenextColumn()
is invoked. -
currentRow
private int currentRowLine position of the cell currently being written. The field is incremented every timenextLine()
is invoked. -
maximalColumnWidths
private int[] maximalColumnWidthsMaximum width for each columns. This array length must be equal to the number of columns in this table. -
lineSeparator
The line separator. We will use the first line separator found in the text to provided by the user, or the system default if none. -
columnSeparator
The column separator, or an empty string if none. -
leftBorder
The left table border, or an empty string if none. -
rightBorder
The right table border, or an empty string if none. -
multiLinesCells
private boolean multiLinesCellsTells if cells can span more than one line. Iftrue
, then EOL characters likes'\n'
move to the next line inside the current cell. Iffalse
, then EOL characters move to the next table row. Default value isfalse
. -
skipLF
private boolean skipLFtrue
if the next character needs to be skipped if equals to'\n'
. -
ownOut
private boolean ownOutSets totrue
at construction time ifAppender.out
has been created by the constructor rather than supplied by the user.
-
-
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
Creates a new table formatter writing in an internal buffer with the specified column separator.- Parameters:
separator
- string to write between columns.
-
TableAppender
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
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
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
-
writeBorder
private void writeBorder(int horizontalBorder, int verticalBorder, char horizontalChar) throws IOException Writes a border or a corner to the underlying stream or buffer.- Parameters:
horizontalBorder
- -1 for left border, +1 for right border, 0 for center.verticalBorder
- -1 for top border, +1 for bottom border, 0 for center.horizontalChar
- character to use for horizontal line.- Throws:
IOException
- if the writing operation failed.
-
isMultiLinesCells
public boolean isMultiLinesCells()Returnstrue
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 tonextColumn()
andnextLine()
calls respectively).
false
.- Parameters:
multiLines
-true
true if EOL are used for line feeds inside current cells, orfalse
if EOL move to the next row.
- If
-
getCellAlignment
public byte getCellAlignment()Returns the alignment of the text inside the current cell. The default value isALIGN_LEFT
.- Returns:
- current cell alignment as one of the
ALIGN_LEFT
,ALIGN_RIGHT
orALIGN_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 thissetCellAlignment(…)
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 theALIGN_LEFT
,ALIGN_RIGHT
orALIGN_CENTER
constants.
-
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 byflush()
.- 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
Writes a single character. IfisMultiLinesCells()
isfalse
(which is the default), then:- Tabulations (
'\t'
) are replaced by calls tonextColumn()
. - line or paragraph separators are replaced by calls to
nextLine()
.
- Specified by:
append
in interfaceAppendable
- Parameters:
c
- character to write.- Returns:
this
.
- Tabulations (
-
append
Appends the specified character sequence.- Specified by:
append
in interfaceAppendable
- Overrides:
append
in classAppender
- Parameters:
sequence
- the character sequence to append, ornull
.- Returns:
- a reference to this
Appendable
.
-
append
Writes a portion of a character sequence. Tabulations and line separators are interpreted as byappend(char)
.- Specified by:
append
in interfaceAppendable
- 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('-')
ornextLine('═')
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
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 interfaceFlushable
- Throws:
IOException
- if an output operation failed.
-
toString
Returns the content of thisTableAppender
as a string if possible.- If this
TableAppender
has been created without explicitAppendable
, then this method always returns the current table content formatted as a string. - Otherwise, if
Appender.out
implementsCharSequence
or is directly or indirectly a wrapper around aCharSequence
, returns itstoString()
representation. The string will contain this table content only ifflush()
has been invoked prior thistoString()
method. - Otherwise returns the localized "Unavailable content" string.
- If this
-
writeTable
Writes the table without clearing theTableAppender
content. Invoking this method many time would result in the same table being repeated.- Throws:
IOException
-
isEmpty
Checks ifarray
contains onlynull
elements. -
repeat
Repeats a character. Thecount
value may be negative, which is handled as if it was zero.- Parameters:
out
- the stream or buffer where to repeat the character.car
- character to write (usually ' ').count
- number of repetition, negative means 0.- Throws:
IOException
-