Package org.moeaframework.analysis.io

Class MetricFileWriter

java.lang.Object

org.moeaframework.analysis.io.MetricFileWriter

All Implemented Interfaces:

Closeable, AutoCloseable, OutputWriter

public class MetricFileWriter
extends Object
implements OutputWriter

Writes metric files. A metric file is the output of Evaluator and contains on each line one or more metrics separated by whitespace from one parameterization.

This writer can append the results to the file, if a previous file exists. By reading the previous file with a MetricFileReader, this writer will begin appending after the last valid entry. Query the getNumberOfEntries() to determine how many valid entries are contained in the file.

See Also:

• MetricFileReader

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static class	MetricFileWriter.MetricFileWriterSettings	The settings used when writing metric files.

Nested classes/interfaces inherited from interface org.moeaframework.analysis.io.OutputWriter

OutputWriter.OutputWriterSettings

Field Summary

Fields

Modifier and Type	Field	Description
static final int	NUMBER_OF_METRICS	The number of metrics supported by MetricFileWriter.

Constructor Summary

Constructors

Constructor	Description
MetricFileWriter(Indicators indicators, File file, MetricFileWriter.MetricFileWriterSettings settings)	Constructs an output writer for writing metric files to the specified file.

Method Summary

Modifier and Type	Method	Description
void	append(ResultEntry entry)	Evaluates the specified non-dominated population and outputs the resulting metrics to the file.
static MetricFileWriter	append(Indicators indicators, File file)	Opens the metric file in append mode.
void	close()
static int	getMetricIndex(String value)	Gets the index of the metric.
int	getNumberOfEntries()	Returns the number of entries in the file.
static MetricFileWriter	overwrite(Indicators indicators, File file)	Opens the metric file in overwrite mode.

Methods inherited from class java.lang.Object

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

Field Details

NUMBER_OF_METRICS

public static final int NUMBER_OF_METRICS

The number of metrics supported by MetricFileWriter.

See Also:

• Constant Field Values

Constructor Details

MetricFileWriter

public MetricFileWriter(Indicators indicators,
 File file,
 MetricFileWriter.MetricFileWriterSettings settings)
                 throws IOException

Constructs an output writer for writing metric files to the specified file. If the file already exists, a cleanup operation is first performed. The cleanup operation removes any invalid entries from the file. The getNumberOfEntries() can then be used to resume evaluation from the last recorded entry.

Parameters:

indicators - the indicators to evaluate

file - the file to which the metrics are written

settings - the settings for writing metric files

Throws:

IOException - if an I/O error occurred

Method Details

getNumberOfEntries

public int getNumberOfEntries()

Description copied from interface: OutputWriter

Returns the number of entries in the file. If the file already existed, this returns the number of complete entries in the output file. This value is incremented on every invocation to the OutputWriter.append(org.moeaframework.analysis.io.ResultEntry) method.

Specified by:

getNumberOfEntries in interface OutputWriter

Returns:

the number of entries in the file

append

public void append(ResultEntry entry)

Evaluates the specified non-dominated population and outputs the resulting metrics to the file.

Specified by:

append in interface OutputWriter

Parameters:

entry - the non-dominated population and optional attributes

getMetricIndex

public static int getMetricIndex(String value)

Gets the index of the metric. This should match the order that columns are written in append(ResultEntry).

Parameters:

value - the metric

Returns:

the index of the metric

close

public void close()

Specified by:

close in interface AutoCloseable

Specified by:

close in interface Closeable

append

public static MetricFileWriter append(Indicators indicators,
 File file)
                               throws IOException

Opens the metric file in append mode. If the file already exists, this writer will validate the contents, remove any invalid entries at the end of the file, and report the number of valid entries in the file.

Parameters:

indicators - the indicators to evaluate

file - the file

Returns:

the metric file writer

Throws:

IOException - if an I/O error occurred

overwrite

public static MetricFileWriter overwrite(Indicators indicators,
 File file)
                                  throws IOException

Opens the metric file in overwrite mode. Any existing file will be deleted.

Parameters:

indicators - the indicators to evaluate

file - the file

Returns:

the metric file writer

Throws:

IOException - if an I/O error occurred