propertyset.java

java ant的源码！非常值得看的源码

    public Mapper getMapper() {
        return isReference() ? getRef().mapper : mapper;
    }

    /**
     * Convert the system properties to a hashtable.
     * Use propertynames to get the list of properties (including
     * default ones).
     */
    private Hashtable getAllSystemProperties() {
        Hashtable ret = new Hashtable();
        for (Enumeration e = System.getProperties().propertyNames();
             e.hasMoreElements();) {
            String name = (String) e.nextElement();
            ret.put(name, System.getProperties().getProperty(name));
        }
        return ret;
    }

    /**
     * This is the operation to get the existing or recalculated properties.
     * @return the properties for this propertyset.
     */
    public Properties getProperties() {
        if (isReference()) {
            return getRef().getProperties();
        }
        Set names = null;
        Project prj = getProject();
        Hashtable props =
            prj == null ? getAllSystemProperties() : prj.getProperties();

        //quick & dirty, to make nested mapped p-sets work:
        for (Enumeration e = setRefs.elements(); e.hasMoreElements();) {
            PropertySet set = (PropertySet) e.nextElement();
            props.putAll(set.getProperties());
        }

        if (getDynamic() || cachedNames == null) {
            names = new HashSet();
            addPropertyNames(names, props);
            // Add this PropertySet's nested PropertySets' property names.
            for (Enumeration e = setRefs.elements(); e.hasMoreElements();) {
                PropertySet set = (PropertySet) e.nextElement();
                names.addAll(set.getProperties().keySet());
            }
            if (negate) {
                //make a copy...
                HashSet complement = new HashSet(props.keySet());
                complement.removeAll(names);
                names = complement;
            }
            if (!getDynamic()) {
                cachedNames = names;
            }
        } else {
            names = cachedNames;
        }
        FileNameMapper m = null;
        Mapper myMapper = getMapper();
        if (myMapper != null) {
            m = myMapper.getImplementation();
        }
        Properties properties = new Properties();
        //iterate through the names, get the matching values
        for (Iterator iter = names.iterator(); iter.hasNext();) {
            String name = (String) iter.next();
            String value = (String) props.get(name);
            if (value != null) {
                // may be null if a system property has been added
                // after the project instance has been initialized
                if (m != null) {
                    //map the names
                    String[] newname = m.mapFileName(name);
                    if (newname != null) {
                        name = newname[0];
                    }
                }
                properties.setProperty(name, value);
            }
        }
        return properties;
    }

    /**
     * @param  names the output Set to fill with the property names
     *         matching this PropertySet selection criteria.
     * @param  properties the current Project properties, passed in to
     *         avoid needless duplication of the Hashtable during recursion.
     */
    private void addPropertyNames(Set names, Hashtable properties) {
        // Add this PropertySet's property names.
        for (Enumeration e = ptyRefs.elements(); e.hasMoreElements();) {
            PropertyRef r = (PropertyRef) e.nextElement();
            if (r.name != null) {
                if (properties.get(r.name) != null) {
                    names.add(r.name);
                }
            } else if (r.prefix != null) {
                for (Enumeration p = properties.keys(); p.hasMoreElements();) {
                    String name = (String) p.nextElement();
                    if (name.startsWith(r.prefix)) {
                        names.add(name);
                    }
                }
            } else if (r.regex != null) {
                RegexpMatcherFactory matchMaker = new RegexpMatcherFactory();
                RegexpMatcher matcher = matchMaker.newRegexpMatcher();
                matcher.setPattern(r.regex);
                for (Enumeration p = properties.keys(); p.hasMoreElements();) {
                    String name = (String) p.nextElement();
                    if (matcher.matches(name)) {
                        names.add(name);
                    }
                }
            } else if (r.builtin != null) {

                if (r.builtin.equals(BuiltinPropertySetName.ALL)) {
                    names.addAll(properties.keySet());
                } else if (r.builtin.equals(BuiltinPropertySetName.SYSTEM)) {
                    names.addAll(System.getProperties().keySet());
                } else if (r.builtin.equals(BuiltinPropertySetName
                                              .COMMANDLINE)) {
                    names.addAll(getProject().getUserProperties().keySet());
                } else {
                    throw new BuildException("Impossible: Invalid builtin "
                                             + "attribute!");
                }
            } else {
                throw new BuildException("Impossible: Invalid PropertyRef!");
            }
        }
    }

    /**
     * Performs the check for circular references and returns the
     * referenced PropertySet.
     * @return the referenced PropertySet.
     */
    protected PropertySet getRef() {
        return (PropertySet) getCheckedRef(PropertySet.class, "propertyset");
    }

    /**
     * Sets the value of the refid attribute.
     *
     * @param  r the reference this datatype should point to.
     * @throws BuildException if another attribute was set, since
     *         refid and all other attributes are mutually exclusive.
     */
    public final void setRefid(Reference r) {
        if (!noAttributeSet) {
            throw tooManyAttributes();
        }
        super.setRefid(r);
    }

    /**
     * Ensures this data type is not a reference.
     *
     * <p>Calling this method as the first line of every bean method of
     * this data type (setXyz, addXyz, createXyz) ensure proper handling
     * of the refid attribute.</p>
     *
     * @throws BuildException if the refid attribute was already set, since
     *         refid and all other attributes are mutually exclusive.
     */
    protected final void assertNotReference() {
        if (isReference()) {
            throw tooManyAttributes();
        }
        noAttributeSet = false;
    }

    /**
     * Flag which tracks whether any attribute has been set; used by
     * {@link #assertNotReference()} and {@link #setRefid(Reference)}.
     */
    private boolean noAttributeSet = true;

    /**
     * Used for propertyref's builtin attribute.
     */
    public static class BuiltinPropertySetName extends EnumeratedAttribute {
        static final String ALL = "all";
        static final String SYSTEM = "system";
        static final String COMMANDLINE = "commandline";
        /** {@inheritDoc}. */
        public String[] getValues() {
            return new String[] {ALL, SYSTEM, COMMANDLINE};
        }
    }

    /**
     * A debug toString.
     * This gets a comma separated list of key=value pairs for
     * the properties in the set.
     * The output order is sorted according to the keys' <i>natural order</i>.
     * @return a string rep of this object.
     */
    public String toString() {
        StringBuffer b = new StringBuffer();
        TreeMap sorted = new TreeMap(getProperties());
        for (Iterator i = sorted.entrySet().iterator(); i.hasNext();) {
            Map.Entry e = (Map.Entry) i.next();
            if (b.length() != 0) {
                b.append(", ");
            }
            b.append(e.getKey().toString());
            b.append("=");
            b.append(e.getValue().toString());
        }
        return b.toString();
    }

    /**
     * Fulfill the ResourceCollection interface.
     * @return an Iterator of Resources.
     * @since Ant 1.7
     */
    public Iterator iterator() {
        final Enumeration e = getProperties().propertyNames();
        return new Iterator() {
            public boolean hasNext() {
                return e.hasMoreElements();
            }
            public Object next() {
                return new PropertyResource(getProject(), (String) e.nextElement());
            }
            public void remove() {
                throw new UnsupportedOperationException();
            }
        };
    }

    /**
     * Fulfill the ResourceCollection contract.
     * @return the size of this ResourceCollection.
     */
    public int size() {
        return isReference() ? getRef().size() : getProperties().size();
    }

    /**
     * Fulfill the ResourceCollection contract.
     * @return whether this is a filesystem-only resource collection.
     */
    public boolean isFilesystemOnly() {
        return isReference() && getRef().isFilesystemOnly();
    }

}