projecthelper.java

Use the links below to download a source distribution of Ant from one of our mirrors. It is good pra

     * @return the current context class loader, or <code>null</code>
     * if the context class loader is unavailable.
     */
    public static ClassLoader getContextClassLoader() {
        return LoaderUtils.isContextLoaderAvailable() ? LoaderUtils.getContextClassLoader() : null;
    }

    // -------------------- Static utils, used by most helpers ----------------

    /**
     * Configures an object using an introspection handler.
     *
     * @param target The target object to be configured.
     *               Must not be <code>null</code>.
     * @param attrs  A list of attributes to configure within the target.
     *               Must not be <code>null</code>.
     * @param project The project containing the target.
     *                Must not be <code>null</code>.
     *
     * @deprecated since 1.6.x.
     *             Use IntrospectionHelper for each property.
     *
     * @exception BuildException if any of the attributes can't be handled by
     *                           the target
     */
    public static void configure(Object target, AttributeList attrs,
                                 Project project) throws BuildException {
        if (target instanceof TypeAdapter) {
            target = ((TypeAdapter) target).getProxy();
        }
        IntrospectionHelper ih = IntrospectionHelper.getHelper(project, target.getClass());

        for (int i = 0, length = attrs.getLength(); i < length; i++) {
            // reflect these into the target
            String value = replaceProperties(project, attrs.getValue(i), project.getProperties());
            try {
                ih.setAttribute(project, target, attrs.getName(i).toLowerCase(Locale.US), value);
            } catch (BuildException be) {
                // id attribute must be set externally
                if (!attrs.getName(i).equals("id")) {
                    throw be;
                }
            }
        }
    }

    /**
     * Adds the content of #PCDATA sections to an element.
     *
     * @param project The project containing the target.
     *                Must not be <code>null</code>.
     * @param target  The target object to be configured.
     *                Must not be <code>null</code>.
     * @param buf A character array of the text within the element.
     *            Will not be <code>null</code>.
     * @param start The start element in the array.
     * @param count The number of characters to read from the array.
     *
     * @exception BuildException if the target object doesn't accept text
     */
    public static void addText(Project project, Object target, char[] buf,
        int start, int count) throws BuildException {
        addText(project, target, new String(buf, start, count));
    }

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

        if (text == null) {
            return;
        }
        if (target instanceof TypeAdapter) {
            target = ((TypeAdapter) target).getProxy();
        }
        IntrospectionHelper.getHelper(project, target.getClass()).addText(project, target, text);
    }

    /**
     * Stores a configured child element within its parent object.
     *
     * @param project Project containing the objects.
     *                May be <code>null</code>.
     * @param parent  Parent object to add child to.
     *                Must not be <code>null</code>.
     * @param child   Child object to store in parent.
     *                Should not be <code>null</code>.
     * @param tag     Name of element which generated the child.
     *                May be <code>null</code>, in which case
     *                the child is not stored.
     */
    public static void storeChild(Project project, Object parent, Object child, String tag) {
        IntrospectionHelper ih = IntrospectionHelper.getHelper(project, parent.getClass());
        ih.storeElement(project, parent, child, tag);
    }

    /**
     * Replaces <code>${xxx}</code> style constructions in the given value with
     * the string value of the corresponding properties.
     *
     * @param project The project containing the properties to replace.
     *                Must not be <code>null</code>.
     *
     * @param value The string to be scanned for property references.
     *              May be <code>null</code>.
     *
     * @exception BuildException if the string contains an opening
     *                           <code>${</code> without a closing
     *                           <code>}</code>
     * @return the original string with the properties replaced, or
     *         <code>null</code> if the original string is <code>null</code>.
     *
     * @deprecated since 1.6.x.
     *             Use project.replaceProperties().
     * @since 1.5
     */
     public static String replaceProperties(Project project, String value) throws BuildException {
        // needed since project properties are not accessible
         return project.replaceProperties(value);
     }

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

    /**
     * Parses a string containing <code>${xxx}</code> style property
     * references into two lists. The first list is a collection
     * of text fragments, while the other is a set of string property names.
     * <code>null</code> entries in the first list indicate a property
     * reference from the second list.
     *
     * @param value     Text to parse. Must not be <code>null</code>.
     * @param fragments List to add text fragments to.
     *                  Must not be <code>null</code>.
     * @param propertyRefs List to add property names to.
     *                     Must not be <code>null</code>.
     *
     * @deprecated since 1.6.x.
     *             Use PropertyHelper.
     * @exception BuildException if the string contains an opening
     *                           <code>${</code> without a closing <code>}</code>
     */
    public static void parsePropertyString(String value, Vector fragments, Vector propertyRefs)
            throws BuildException {
        PropertyHelper.parsePropertyStringDefault(value, fragments, propertyRefs);
    }

    /**
     * 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.
     * @param uri   The namepace URI
     * @param name  The localname
     * @return      The stringified form of the ns name
     */
    public static String genComponentName(String uri, String name) {
        if (uri == null || uri.equals("") || uri.equals(ANT_CORE_URI)) {
            return name;
        }
        return uri + ":" + name;
    }

    /**
     * extract a uri from a component name
     *
     * @param componentName  The stringified form for {uri, name}
     * @return               The uri or "" if not present
     */
    public static String extractUriFromComponentName(String componentName) {
        if (componentName == null) {
            return "";
        }
        int index = componentName.lastIndexOf(':');
        if (index == -1) {
            return "";
        }
        return componentName.substring(0, index);
    }

    /**
     * extract the element name from a component name
     *
     * @param componentName  The stringified form for {uri, name}
     * @return               The element name of the component
     */
    public static String extractNameFromComponentName(String componentName) {
        int index = componentName.lastIndexOf(':');
        if (index == -1) {
            return componentName;
        }
        return componentName.substring(index + 1);
    }

    /**
     * Add location to build exception.
     * @param ex the build exception, if the build exception
     *           does not include
     * @param newLocation the location of the calling task (may be null)
     * @return 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
     */
    public static BuildException addLocationToBuildException(
            BuildException ex, Location newLocation) {
        if (ex.getLocation() == null || ex.getMessage() == null) {
            return ex;
        }
        String errorMessage
            = "The following error occurred while executing this line:"
            + System.getProperty("line.separator")
            + ex.getLocation().toString()
            + ex.getMessage();
        if (newLocation == null) {
            return new BuildException(errorMessage, ex);
        }
        return new BuildException(errorMessage, ex, newLocation);
    }
}