tap.formatter

Class TextFormat

java.lang.Object

tap.formatter.TextFormat

All Implemented Interfaces:

OutputFormat

public class TextFormat
extends java.lang.Object
implements OutputFormat

Format any given query (table) result into a simple table ASCII representation (columns' width are adjusted so that all columns are well aligned and of the same width).

Version:

2.3 (11/2018)

Author:

Grégory Mantelet (CDS;ARI)

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
protected static class	TextFormat.LineFormatter Lets format a line and then write it in the given BufferedWriter.

Field Summary

Fields

Modifier and Type	Field and Description
protected int[]	alignment How all columns must be aligned.
protected static char	COL_SEP Internal column separator.
protected ServiceConnection	service The ServiceConnection to use (for the log and to have some information about the service (particularly: name, description).

Constructor Summary

Constructors

Constructor and Description
TextFormat(ServiceConnection service) Build a TextFormat.
TextFormat(ServiceConnection service, int[] customAlignment) Build a TextFormat.

Method Summary

Modifier and Type	Method and Description
java.lang.String	getDescription() Gets a description of this format.
java.lang.String	getFileExtension() Gets a file extension for this format.
protected java.lang.String	getHeader(TableIterator result, TAPExecutionReport execReport, java.lang.Thread thread) Get the whole header (one row whose columns are just the columns' name).
java.lang.String	getMimeType() Gets the MIME type corresponding to this format.
java.lang.String	getShortMimeType() Gets a short expression of its MIME type.
protected boolean	writeData(TableIterator queryResult, LargeAsciiTable asciiTable, TAPExecutionReport execReport, java.lang.Thread thread) Write all the data rows into the given LargeAsciiTable object.
protected void	writeFieldValue(java.lang.Object value, DBColumn tapCol, java.lang.StringBuffer line) Writes the given field value in the given buffer.
void	writeResult(TableIterator result, java.io.OutputStream output, TAPExecutionReport execReport, java.lang.Thread thread) Formats the given query result and writes it in the given output stream.

Methods inherited from class java.lang.Object

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

Field Detail

COL_SEP

protected static final char COL_SEP

Internal column separator. Note: the output separator is however always a |.

Since:

2.0

See Also:

Constant Field Values

alignment

protected int[] alignment

How all columns must be aligned.

Since:

2.3

See Also:

LargeAsciiTable.streamAligned(LineProcessor, int[])

service

protected final ServiceConnection service

The ServiceConnection to use (for the log and to have some information about the service (particularly: name, description).

Constructor Detail

TextFormat

public TextFormat(ServiceConnection service)
           throws java.lang.NullPointerException

Build a TextFormat.

Note: All columns values will be aligned on the left. To change this default alignment, use TextFormat(ServiceConnection, int[]) instead.

Parameters:

service - Description of the TAP service.

Throws:

java.lang.NullPointerException - If the given service connection is NULL.

TextFormat

public TextFormat(ServiceConnection service,
                  int[] customAlignment)
           throws java.lang.NullPointerException

Build a TextFormat.

Parameters:

service - Description of the TAP service.

customAlignment - How columns must be aligned. (see LargeAsciiTable.streamAligned(LineProcessor, int[]) to know the rules about this array)

Throws:

java.lang.NullPointerException - If the given service connection is NULL.

Since:

2.3

Method Detail

getMimeType

public java.lang.String getMimeType()

Description copied from interface: OutputFormat

Gets the MIME type corresponding to this format.

Specified by:

getMimeType in interface OutputFormat

Returns:

Its MIME type (MUST BE DIFFERENT FROM NULL).

getShortMimeType

public java.lang.String getShortMimeType()

Description copied from interface: OutputFormat

Gets a short expression of its MIME type.

Specified by:

getShortMimeType in interface OutputFormat

Returns:

Its short MIME type.

getDescription

public java.lang.String getDescription()

Description copied from interface: OutputFormat

Gets a description of this format.

Specified by:

getDescription in interface OutputFormat

Returns:

Its description.

getFileExtension

public java.lang.String getFileExtension()

Description copied from interface: OutputFormat

Gets a file extension for this format.

Specified by:

getFileExtension in interface OutputFormat

Returns:

Its file extension.

writeResult

public void writeResult(TableIterator result,
                        java.io.OutputStream output,
                        TAPExecutionReport execReport,
                        java.lang.Thread thread)
                 throws TAPException,
                        java.io.IOException,
                        java.lang.InterruptedException

Description copied from interface: OutputFormat

Formats the given query result and writes it in the given output stream.

Note: the given output stream should not be closed at the end of this function. It is up to the called to do it.

Specified by:

writeResult in interface OutputFormat

Parameters:

result - The raw (table) result to format.

output - The output stream (a ServletOutputStream or a stream on a file) in which the formatted result must be written.

execReport - The report of the execution of the TAP query whose the result must be now written.

thread - The thread which has asked the result writing.

Throws:

TAPException - If there is an error while formatting the query result.

java.io.IOException - If any error occurs while writing into the given stream.

java.lang.InterruptedException - If the query has been interrupted/aborted.

getHeader

protected java.lang.String getHeader(TableIterator result,
                                     TAPExecutionReport execReport,
                                     java.lang.Thread thread)
                              throws TAPException

Get the whole header (one row whose columns are just the columns' name).

Parameters:

result - Result to write later (but it contains also metadata that was extracted from the result itself).

execReport - Execution report (which contains the metadata extracted/guessed from the ADQL query).

thread - Thread which has asked for this formatting (it must be used in order to test the Thread.isInterrupted() flag and so interrupt everything if need).

Returns:

All the written metadata.

Throws:

TAPException - If any other error occurs.

writeData

protected boolean writeData(TableIterator queryResult,
                            LargeAsciiTable asciiTable,
                            TAPExecutionReport execReport,
                            java.lang.Thread thread)
                     throws java.io.IOException,
                            TAPException,
                            java.lang.InterruptedException

Write all the data rows into the given LargeAsciiTable object.

Parameters:

queryResult - Result to write.

asciiTable - Output in which the rows (as string) must be written.

execReport - Execution report (which contains the maximum allowed number of records to output).

thread - Thread which has asked for this formatting (it must be used in order to test the Thread.isInterrupted() flag and so interrupt everything if need).

Returns:

true if an overflow (i.e. nbDBRows > MAXREC) is detected, false otherwise.

Throws:

java.lang.InterruptedException - If the thread has been interrupted.

TAPException - If any other error occurs.

java.io.IOException

writeFieldValue

protected void writeFieldValue(java.lang.Object value,
                               DBColumn tapCol,
                               java.lang.StringBuffer line)

Writes the given field value in the given buffer.

Parameters:

value - The value to write.

tapCol - The corresponding column metadata.

line - The buffer in which the field value must be written.