org.apache.maven.shared.incremental

Class IncrementalBuildHelper

java.lang.Object

org.apache.maven.shared.incremental.IncrementalBuildHelper

public class IncrementalBuildHelper
extends Object

Various helper methods to support incremental builds

Field Summary

Fields

Modifier and Type	Field and Description
static String	CREATED_FILES_LST_FILENAME

Constructor Summary

Constructors

Constructor and Description
IncrementalBuildHelper(org.apache.maven.plugin.MojoExecution mojoExecution, org.apache.maven.project.MavenProject mavenProject)
IncrementalBuildHelper(org.apache.maven.plugin.MojoExecution mojoExecution, org.apache.maven.execution.MavenSession mavenSession)

Method Summary

Modifier and Type	Method and Description
void	afterRebuildExecution(IncrementalBuildHelperRequest incrementalBuildHelperRequest) This method collects and stores all information about files changed since the call to beforeRebuildExecution(org.apache.maven.shared.incremental.IncrementalBuildHelperRequest).
String[]	beforeRebuildExecution(IncrementalBuildHelperRequest incrementalBuildHelperRequest) This method shall get invoked before the actual Mojo task gets triggered, e.g.
org.apache.maven.shared.utils.io.DirectoryScanner	getDirectoryScanner() Get the existing DirectoryScanner used by this helper, or create new a DirectoryScanner if none is yet set.
File	getMojoStatusDirectory() We use a specific status directory for each Mojo execution to store state which is needed during the next build invocation run.
boolean	inputFileTreeChanged(org.apache.maven.shared.utils.io.DirectoryScanner dirScanner) Detect whether the list of detected files picked up by the DirectoryScanner has changed since the last build.
boolean	inputFileTreeChanged(IncrementalBuildHelperRequest incrementalBuildHelperRequest) Detect whether the list of detected files has changed since the last build.
void	setDirectoryScanner(org.apache.maven.shared.utils.io.DirectoryScanner directoryScanner) Set the DirectoryScanner which shall get used by this build helper.

Methods inherited from class java.lang.Object

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

Field Detail

CREATED_FILES_LST_FILENAME

public static final String CREATED_FILES_LST_FILENAME

See Also:

Constant Field Values

Constructor Detail

IncrementalBuildHelper

public IncrementalBuildHelper(org.apache.maven.plugin.MojoExecution mojoExecution,
                              org.apache.maven.execution.MavenSession mavenSession)

IncrementalBuildHelper

public IncrementalBuildHelper(org.apache.maven.plugin.MojoExecution mojoExecution,
                              org.apache.maven.project.MavenProject mavenProject)

Method Detail

getDirectoryScanner

public org.apache.maven.shared.utils.io.DirectoryScanner getDirectoryScanner()

Get the existing DirectoryScanner used by this helper, or create new a DirectoryScanner if none is yet set. The DirectoryScanner is used for detecting changes in a directory

setDirectoryScanner

public void setDirectoryScanner(org.apache.maven.shared.utils.io.DirectoryScanner directoryScanner)

Set the DirectoryScanner which shall get used by this build helper.

Parameters:

directoryScanner -

getMojoStatusDirectory

public File getMojoStatusDirectory()
                            throws org.apache.maven.plugin.MojoExecutionException

We use a specific status directory for each Mojo execution to store state which is needed during the next build invocation run.

Returns:

the directory for storing status information of the current Mojo execution.

Throws:

org.apache.maven.plugin.MojoExecutionException

inputFileTreeChanged

public boolean inputFileTreeChanged(IncrementalBuildHelperRequest incrementalBuildHelperRequest)
                             throws org.apache.maven.plugin.MojoExecutionException

Detect whether the list of detected files has changed since the last build. We simply load the list of files for the previous build from a status file and compare it with the new list. Afterwards we store the new list in the status file.

Parameters:

incrementalBuildHelperRequest -

Returns:

true if the set of inputFiles got changed since the last build.

Throws:

org.apache.maven.plugin.MojoExecutionException

inputFileTreeChanged

public boolean inputFileTreeChanged(org.apache.maven.shared.utils.io.DirectoryScanner dirScanner)
                             throws org.apache.maven.plugin.MojoExecutionException

Detect whether the list of detected files picked up by the DirectoryScanner has changed since the last build. We simply load the list of files for the previous build from a status file and compare it with the result of the new DirectoryScanner#scan(). Afterwards we store the new list in the status file.

Parameters:

dirScanner -

Returns:

true if the set of inputFiles got changed since the last build.

Throws:

org.apache.maven.plugin.MojoExecutionException

beforeRebuildExecution

public String[] beforeRebuildExecution(IncrementalBuildHelperRequest incrementalBuildHelperRequest)
                                throws org.apache.maven.plugin.MojoExecutionException

This method shall get invoked before the actual Mojo task gets triggered, e.g. the actual compile in maven-compiler-plugin.

Attention: This method shall only get invoked if the plugin re-creates all the output.

It first picks up the list of files created in the previous build and delete them. This step is necessary to prevent left-overs. After that we take a 'directory snapshot' (list of all files which exist in the outputDirectory after the clean).

After the actual Mojo task got executed you should invoke the method afterRebuildExecution(org.apache.maven.shared.incremental.IncrementalBuildHelperRequest) to collect the list of files which got changed by this task.

Parameters:

incrementalBuildHelperRequest -

Returns:

all files which got created in the previous build and have been deleted now.

Throws:

org.apache.maven.plugin.MojoExecutionException

afterRebuildExecution

public void afterRebuildExecution(IncrementalBuildHelperRequest incrementalBuildHelperRequest)
                           throws org.apache.maven.plugin.MojoExecutionException

This method collects and stores all information about files changed since the call to beforeRebuildExecution(org.apache.maven.shared.incremental.IncrementalBuildHelperRequest).

Attention: This method shall only get invoked if the plugin re-creates all the output.

Parameters:

incrementalBuildHelperRequest - will contains file sources to store if create files are not yet stored

Throws:

org.apache.maven.plugin.MojoExecutionException