ProjectHelper (Apache Ant API)
Description: declaration: package: org.apache.tools.ant, class: ProjectHelper

# Class ProjectHelper

java.lang.Object
org.apache.tools.ant.ProjectHelper

Direct Known Subclasses:
  `ProjectHelper2, ProjectHelperImpl`

public class ProjectHelper extends Object
Configures a Project (complete with Targets and Tasks) based on a build file. It'll rely on a plugin to do the actual processing of the file.

This class also provide static wrappers for common introspection.

- ## Nested Class Summary

  Nested Classes
  Modifier and Type
  Class
  Description
  `static final class`
  `ProjectHelper.OnMissingExtensionPoint`
  Possible value for target's onMissingExtensionPoint attribute.

- ## Field Summary

  Fields
  Modifier and Type
  Field
  Description
  `static final String`
  `ANT_ATTRIBUTE_URI`
  The URI for ant specific attributes
  `static final String`
  `ANT_CORE_URI`
  The URI for ant name space
  `static final String`
  `ANT_CURRENT_URI`
  The URI for antlib current definitions
  `static final String`
  `ANT_TYPE`
  Polymorphic attribute
  `static final String`
  `ANTLIB_URI`
  Deprecated.
  use MagicNames.ANTLIB_PREFIX
  `static final String`
  `HELPER_PROPERTY`
  Deprecated.
  use MagicNames.PROJECT_HELPER_CLASS
  `static final String`
  `PROJECTHELPER_REFERENCE`
  Deprecated.
  use MagicNames.REFID_PROJECT_HELPER
  `static final String`
  `SERVICE_ID`
  Deprecated.
  use MagicNames.PROJECT_HELPER_SERVICE
  `static final String`
  `USE_PROJECT_NAME_AS_TARGET_PREFIX`
  constant to denote use project name as target prefix

- ## Constructor Summary

  Constructors
  Constructor
  Description
  `ProjectHelper()`

- ## Method Summary

  Modifier and Type
  Method
  Description
  `static BuildException`
  `addLocationToBuildException(BuildException ex, Location newLocation)`
  Add location to build exception.
  `static void`
  `addText(Project project, Object target, char[] buf, int start, int count)`
  Adds the content of #PCDATA sections to an element.
  `static void`
  `addText(Project project, Object target, String text)`
  Adds the content of #PCDATA sections to an element.
  `boolean`
  `canParseAntlibDescriptor(Resource r)`
  Whether this instance of ProjectHelper can parse an Antlib descriptor given by the URL and return its content as an UnknownElement ready to be turned into an Antlib task.
  `boolean`
  `canParseBuildFile(Resource buildFile)`
  Check if the helper supports the kind of file.
  `static void`
  `configure(Object target, AttributeList attrs, Project project)`
  Deprecated.
  since 1.6.x.
  `static void`
  `configureProject(Project project, File buildFile)`
  Configures the project with the contents of the specified build file.
  `static String`
  `extractNameFromComponentName(String componentName)`
  extract the element name from a component name
  `static String`
  `extractUriFromComponentName(String componentName)`
  extract a uri from a component name
  `static String`
  `genComponentName(String uri, String name)`
  Map a namespaced {uri,name} to an internal string format.
  `static ClassLoader`
  `getContextClassLoader()`
  Deprecated.
  since 1.6.x.
  `static String`
  `getCurrentPrefixSeparator()`
  The separator between the prefix and the target name.
  `static String`
  `getCurrentTargetPrefix()`
  The prefix to prepend to imported target names.
  `String`
  `getDefaultBuildFile()`
  The file name of the build script to be parsed if none specified on the command line
  `List<String[]>`
  `getExtensionStack()`
  Extension stack.
  `Vector<Object>`
  `getImportStack()`
  Import stack.
  `static ProjectHelper`
  `getProjectHelper()`
  Get the first project helper found in the classpath
  `static boolean`
  `isInIncludeMode()`
  Whether the current file should be read in include as opposed to import mode.
  `static String`
  `nsToComponentName(String ns)`
  Convert an attribute namespace to a "component name".
  `void`
  `parse(Project project, Object source)`
  Parses the project file, configuring the project as it goes.
  `UnknownElement`
  `parseAntlibDescriptor(Project containingProject, Resource source)`
  Parse the given URL as an antlib descriptor and return the content as something that can be turned into an Antlib task.
  `static void`
  `parsePropertyString(String value, Vector<String> fragments, Vector<String> propertyRefs)`
  Deprecated.
  since 1.6.x.
  `static String`
  `replaceProperties(Project project, String value)`
  Deprecated.
  since 1.6.x.
  `static String`
  `replaceProperties(Project project, String value, Hashtable<String,Object> keys)`
  Deprecated.
  since 1.6.x.
  `void`
  `resolveExtensionOfAttributes(Project project)`
  Check extensionStack and inject all targets having extensionOf attributes into extensionPoint.
  `static void`
  `setCurrentPrefixSeparator(String sep)`
  Sets the separator between the prefix and the target name.
  `static void`
  `setCurrentTargetPrefix(String prefix)`
  Sets the prefix to prepend to imported target names.
  `static void`
  `setInIncludeMode(boolean includeMode)`
  Sets whether the current file should be read in include as opposed to import mode.
  `static void`
  `storeChild(Project project, Object parent, Object child, String tag)`
  Stores a configured child element within its parent object.

  ### Methods inherited from class Object

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

- ## Field Details

  - ### ANT_CORE_URI

    public static final String ANT_CORE_URI
    The URI for ant name space
    See Also:
      - Constant Field Values

  - ### ANT_CURRENT_URI

    public static final String ANT_CURRENT_URI
    The URI for antlib current definitions
    See Also:
      - Constant Field Values

  - ### ANT_ATTRIBUTE_URI

    public static final String ANT_ATTRIBUTE_URI
    The URI for ant specific attributes
    Since:
      Ant 1.9.1
    See Also:
      - Constant Field Values

  - ### ANTLIB_URI

    @Deprecated public static final String ANTLIB_URI
    Deprecated.
    use MagicNames.ANTLIB_PREFIX
    The URI for defined types/tasks - the format is antlib:<package>
    See Also:
      - Constant Field Values

  - ### ANT_TYPE

    public static final String ANT_TYPE
    Polymorphic attribute
    See Also:
      - Constant Field Values

  - ### HELPER_PROPERTY

    @Deprecated public static final String HELPER_PROPERTY
    Deprecated.
    use MagicNames.PROJECT_HELPER_CLASS
    Name of JVM system property which provides the name of the ProjectHelper class to use.
    See Also:
      - Constant Field Values

  - ### SERVICE_ID

    @Deprecated public static final String SERVICE_ID
    Deprecated.
    use MagicNames.PROJECT_HELPER_SERVICE
    The service identifier in jars which provide Project Helper implementations.
    See Also:
      - Constant Field Values

  - ### PROJECTHELPER_REFERENCE

    @Deprecated public static final String PROJECTHELPER_REFERENCE
    Deprecated.
    use MagicNames.REFID_PROJECT_HELPER
    name of project helper reference that we add to a project
    See Also:
      - Constant Field Values

  - ### USE_PROJECT_NAME_AS_TARGET_PREFIX

    public static final String USE_PROJECT_NAME_AS_TARGET_PREFIX
    constant to denote use project name as target prefix
    Since:
      Ant 1.9.1
    See Also:
      - Constant Field Values

- ## Constructor Details

  - ### ProjectHelper

    public ProjectHelper()

- ## Method Details

  - ### configureProject

    public static void configureProject(Project project, File buildFile) throws BuildException
    Configures the project with the contents of the specified build file.
    Parameters:
      `project` - The project to configure. Must not be `null`.
      `buildFile` - A build file giving the project's configuration. Must not be `null`.
    Throws:
      `BuildException` - if the configuration is invalid or cannot be read

  - ### getImportStack

    public Vector<Object> getImportStack()
    Import stack. Used to keep track of imported files. Error reporting should display the import path.
    Returns:
      the stack of import source objects.

  - ### getExtensionStack

    public List<String[]> getExtensionStack()
    Extension stack. Used to keep track of targets that extend extension points.
    Returns:
      a list of three element string arrays where the first element is the name of the extensionpoint, the second the name of the target and the third the name of the enum like class `ProjectHelper.OnMissingExtensionPoint`.

  - ### getCurrentTargetPrefix

    public static String getCurrentTargetPrefix()
    The prefix to prepend to imported target names.

    May be set by <import>'s as attribute.

    Returns:
      the configured prefix or null
    Since:
      Ant 1.8.0

  - ### setCurrentTargetPrefix

    public static void setCurrentTargetPrefix(String prefix)
    Sets the prefix to prepend to imported target names.
    Parameters:
      `prefix` - String
    Since:
      Ant 1.8.0

  - ### getCurrentPrefixSeparator

    public static String getCurrentPrefixSeparator()
    The separator between the prefix and the target name.

    May be set by <import>'s prefixSeparator attribute.

    Returns:
      String
    Since:
      Ant 1.8.0

  - ### setCurrentPrefixSeparator

    public static void setCurrentPrefixSeparator(String sep)
    Sets the separator between the prefix and the target name.
    Parameters:
      `sep` - String
    Since:
      Ant 1.8.0

  - ### isInIncludeMode

    public static boolean isInIncludeMode()
    Whether the current file should be read in include as opposed to import mode.

    In include mode included targets are only known by their prefixed names and their depends lists get rewritten so that all dependencies get the prefix as well.

    In import mode imported targets are known by an adorned as well as a prefixed name and the unadorned target may be overwritten in the importing build file. The depends list of the imported targets is not modified at all.

    Returns:
      boolean
    Since:
      Ant 1.8.0

  - ### setInIncludeMode

    public static void setInIncludeMode(boolean includeMode)
    Sets whether the current file should be read in include as opposed to import mode.
    Parameters:
      `includeMode` - boolean
    Since:
      Ant 1.8.0

  - ### parse

    public void parse(Project project, Object source) throws BuildException
    Parses the project file, configuring the project as it goes.
    Parameters:
      `project` - The project for the resulting ProjectHelper to configure. Must not be `null`.
      `source` - The source for XML configuration. A helper must support at least File, for backward compatibility. Helpers may support URL, InputStream, etc or specialized types.
    Throws:
      `BuildException` - if the configuration is invalid or cannot be read
    Since:
      Ant1.5

  - ### getProjectHelper

    public static ProjectHelper getProjectHelper()
    Get the first project helper found in the classpath
    Returns:
      an project helper, never `null`
    See Also:
      - `ProjectHelperRepository.getHelpers()`

  - ### getContextClassLoader

    @Deprecated public static ClassLoader getContextClassLoader()
    Deprecated.
    since 1.6.x. Use LoaderUtils.getContextClassLoader()
    JDK1.1 compatible access to the context class loader. Cut & paste from JAXP.
    Returns:
      the current context class loader, or `null` if the context class loader is unavailable.

  - ### configure

    @Deprecated public static void configure(Object target, AttributeList attrs, Project project) throws BuildException
    Deprecated.
    since 1.6.x. Use IntrospectionHelper for each property.
    Configures an object using an introspection handler.
    Parameters:
      `target` - The target object to be configured. Must not be `null`.
      `attrs` - A list of attributes to configure within the target. Must not be `null`.
      `project` - The project containing the target. Must not be `null`.
    Throws:
      `BuildException` - if any of the attributes can't be handled by the target

  - ### addText

    public static void addText(Project project, Object target, char[] buf, int start, int count) throws BuildException
    Adds the content of #PCDATA sections to an element.
    Parameters:
      `project` - The project containing the target. Must not be `null`.
      `target` - The target object to be configured. Must not be `null`.
      `buf` - A character array of the text within the element. Will not be `null`.
      `start` - The start element in the array.
      `count` - The number of characters to read from the array.
    Throws:
      `BuildException` - if the target object doesn't accept text

  - ### addText

    public static void addText(Project project, Object target, String text) throws BuildException
    Adds the content of #PCDATA sections to an element.
    Parameters:
      `project` - The project containing the target. Must not be `null`.
      `target` - The target object to be configured. Must not be `null`.
      `text` - Text to add to the target. May be `null`, in which case this method call is a no-op.
    Throws:
      `BuildException` - if the target object doesn't accept text

  - ### storeChild

    public static void storeChild(Project project, Object parent, Object child, String tag)
    Stores a configured child element within its parent object.
    Parameters:
      `project` - Project containing the objects. May be `null`.
      `parent` - Parent object to add child to. Must not be `null`.
      `child` - Child object to store in parent. Should not be `null`.
      `tag` - Name of element which generated the child. May be `null`, in which case the child is not stored.

  - ### replaceProperties

    @Deprecated public static String replaceProperties(Project project, String value) throws BuildException
    Deprecated.
    since 1.6.x. Use project.replaceProperties().
    Replaces `${xxx}` style constructions in the given value with the string value of the corresponding properties.
    Parameters:
      `project` - The project containing the properties to replace. Must not be `null`.
      `value` - The string to be scanned for property references. May be `null`.
    Returns:
      the original string with the properties replaced, or `null` if the original string is `null`.
    Throws:
      `BuildException` - if the string contains an opening `${` without a closing `}`
    Since:
      1.5

  - ### replaceProperties

    @Deprecated public static String replaceProperties(Project project, String value, Hashtable<String,Object> keys) throws BuildException
    Deprecated.
    since 1.6.x. Use PropertyHelper.
    Replaces `${xxx}` style constructions in the given value with the string value of the corresponding data types.
    Parameters:
      `project` - The container project. This is used solely for logging purposes. Must not be `null`.
      `value` - The string to be scanned for property references. May be `null`, in which case this method returns immediately with no effect.
      `keys` - Mapping (String to Object) of property names to their values. Must not be `null`.
    Returns:
      the original string with the properties replaced, or `null` if the original string is `null`.
    Throws:
      `BuildException` - if the string contains an opening `${` without a closing `}`

  - ### parsePropertyString

    @Deprecated public static void parsePropertyString(String value, Vector<String> fragments, Vector<String> propertyRefs) throws BuildException
    Deprecated.
    since 1.6.x. Use PropertyHelper.
    Parses a string containing `${xxx}` style property references into two lists. The first list is a collection of text fragments, while the other is a set of string property names. `null` entries in the first list indicate a property reference from the second list.

    As of Ant 1.8.0 this method is never invoked by any code inside of Ant itself.

    Parameters:
      `value` - Text to parse. Must not be `null`.
      `fragments` - List to add text fragments to. Must not be `null`.
      `propertyRefs` - List to add property names to. Must not be `null`.
    Throws:
      `BuildException` - if the string contains an opening `${` without a closing `}`

  - ### genComponentName

    public static String genComponentName(String uri, String name)
    Map a namespaced {uri,name} to an internal string format. For BC purposes the names from the ant core uri will be mapped to "name", other names will be mapped to uri + ":" + name.
    Parameters:
      `uri` - The namespace URI
      `name` - The localname
    Returns:
      The stringified form of the ns name

  - ### extractUriFromComponentName

    public static String extractUriFromComponentName(String componentName)
    extract a uri from a component name
    Parameters:
      `componentName` - The stringified form for {uri, name}
    Returns:
      The uri or "" if not present

  - ### extractNameFromComponentName

    public static String extractNameFromComponentName(String componentName)
    extract the element name from a component name
    Parameters:
      `componentName` - The stringified form for {uri, name}
    Returns:
      The element name of the component

  - ### nsToComponentName

    public static String nsToComponentName(String ns)
    Convert an attribute namespace to a "component name".
    Parameters:
      `ns` - the xml namespace uri.
    Returns:
      the converted value.
    Since:
      Ant 1.9.1

  - ### addLocationToBuildException

    public static BuildException addLocationToBuildException(BuildException ex, Location newLocation)
    Add location to build exception.
    Parameters:
      `ex` - the build exception, if the build exception does not include
      `newLocation` - the location of the calling task (may be null)
    Returns:
      a new build exception based in the build exception with location set to newLocation. If the original exception did not have a location, just return the build exception

  - ### canParseAntlibDescriptor

    public boolean canParseAntlibDescriptor(Resource r)
    Whether this instance of ProjectHelper can parse an Antlib descriptor given by the URL and return its content as an UnknownElement ready to be turned into an Antlib task.

    This method should not try to parse the content of the descriptor, the URL is only given as an argument to allow subclasses to decide whether they can support a given URL scheme or not.

    Subclasses that return true in this method must also override `parseAntlibDescriptor`.

    This implementation returns false.

    Parameters:
      `r` - Resource
    Returns:
      boolean
    Since:
      Ant 1.8.0

  - ### parseAntlibDescriptor

    public UnknownElement parseAntlibDescriptor(Project containingProject, Resource source)
    Parse the given URL as an antlib descriptor and return the content as something that can be turned into an Antlib task.
    Parameters:
      `containingProject` - Project
      `source` - Resource
    Returns:
      UnknownElement
    Since:
      ant 1.8.0

  - ### canParseBuildFile

    public boolean canParseBuildFile(Resource buildFile)
    Check if the helper supports the kind of file. Some basic check on the extension's file should be done here.
    Parameters:
      `buildFile` - the file expected to be parsed (never `null`)
    Returns:
      true if the helper supports it
    Since:
      Ant 1.8.0

  - ### getDefaultBuildFile

    public String getDefaultBuildFile()
    The file name of the build script to be parsed if none specified on the command line
    Returns:
      the name of the default file (never `null`)
    Since:
      Ant 1.8.0

  - ### resolveExtensionOfAttributes

    public void resolveExtensionOfAttributes(Project project) throws BuildException
    Check extensionStack and inject all targets having extensionOf attributes into extensionPoint.

    This method allow you to defer injection and have a powerful control of extensionPoint wiring.

    This should be invoked by each concrete implementation of ProjectHelper when the root "buildfile" and all imported/included buildfile are loaded.

    Parameters:
      `project` - The project containing the target. Must not be `null`.
    Throws:
      `BuildException` - if OnMissingExtensionPoint.FAIL and extensionPoint does not exist
    Since:
      1.9
    See Also:
      - `ProjectHelper.OnMissingExtensionPoint`