xmlutils.java

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            if (name != null) {
                out.attribute(null, "name", name);
            }
            out.text(v.toString());
            out.endTag(null, "string");
            return;
        } else if (v instanceof Integer) {
            typeStr = "int";
        } else if (v instanceof Long) {
            typeStr = "long";
        } else if (v instanceof Float) {
            typeStr = "float";
        } else if (v instanceof Double) {
            typeStr = "double";
        } else if (v instanceof Boolean) {
            typeStr = "boolean";
        } else if (v instanceof byte[]) {
            writeByteArrayXml((byte[])v, name, out);
            return;
        } else if (v instanceof int[]) {
            writeIntArrayXml((int[])v, name, out);
            return;
        } else if (v instanceof Map) {
            writeMapXml((Map)v, name, out);
            return;
        } else if (v instanceof List) {
            writeListXml((List)v, name, out);
            return;
        } else if (v instanceof CharSequence) {
            // XXX This is to allow us to at least write something if
            // we encounter styled text...  but it means we will drop all
            // of the styling information. :(
            out.startTag(null, "string");
            if (name != null) {
                out.attribute(null, "name", name);
            }
            out.text(v.toString());
            out.endTag(null, "string");
            return;
        } else {
            throw new RuntimeException("writeValueXml: unable to write value " + v);
        }

        out.startTag(null, typeStr);
        if (name != null) {
            out.attribute(null, "name", name);
        }
        out.attribute(null, "value", v.toString());
        out.endTag(null, typeStr);
    }

    /**
     * Read a HashMap from an InputStream containing XML.  The stream can
     * previously have been written by writeMapXml().
     * 
     * @param in The InputStream from which to read.
     * 
     * @return HashMap The resulting map.
     * 
     * @see #readListXml
     * @see #readValueXml
     * @see #readThisMapXml
     * #see #writeMapXml
     */
    public static final HashMap readMapXml(InputStream in)
    throws XmlPullParserException, java.io.IOException
    {
        XmlPullParser   parser = Xml.newPullParser();
        parser.setInput(in, null);
        return (HashMap)readValueXml(parser, new String[1]);
    }

    /**
     * Read an ArrayList from an InputStream containing XML.  The stream can
     * previously have been written by writeListXml().
     * 
     * @param in The InputStream from which to read.
     * 
     * @return HashMap The resulting list.
     * 
     * @see #readMapXml
     * @see #readValueXml
     * @see #readThisListXml
     * @see #writeListXml
     */
    public static final ArrayList readListXml(InputStream in)
    throws XmlPullParserException, java.io.IOException
    {
        XmlPullParser   parser = Xml.newPullParser();
        parser.setInput(in, null);
        return (ArrayList)readValueXml(parser, new String[1]);
    }

    /**
     * Read a HashMap object from an XmlPullParser.  The XML data could
     * previously have been generated by writeMapXml().  The XmlPullParser
     * must be positioned <em>after</em> the tag that begins the map.
     * 
     * @param parser The XmlPullParser from which to read the map data.
     * @param endTag Name of the tag that will end the map, usually "map".
     * @param name An array of one string, used to return the name attribute
     *             of the map's tag.
     * 
     * @return HashMap The newly generated map.
     * 
     * @see #readMapXml
     */
    public static final HashMap readThisMapXml(XmlPullParser parser, String endTag, String[] name)
    throws XmlPullParserException, java.io.IOException
    {
        HashMap map = new HashMap();

        int eventType = parser.getEventType();
        do {
            if (eventType == parser.START_TAG) {
                Object val = readThisValueXml(parser, name);
                if (name[0] != null) {
                    //System.out.println("Adding to map: " + name + " -> " + val);
                    map.put(name[0], val);
                } else {
                    throw new XmlPullParserException(
                        "Map value without name attribute: " + parser.getName());
                }
            } else if (eventType == parser.END_TAG) {
                if (parser.getName().equals(endTag)) {
                    return map;
                }
                throw new XmlPullParserException(
                    "Expected " + endTag + " end tag at: " + parser.getName());
            }
            eventType = parser.next();
        } while (eventType != parser.END_DOCUMENT);

        throw new XmlPullParserException(
            "Document ended before " + endTag + " end tag");
    }

    /**
     * Read an ArrayList object from an XmlPullParser.  The XML data could
     * previously have been generated by writeListXml().  The XmlPullParser
     * must be positioned <em>after</em> the tag that begins the list.
     * 
     * @param parser The XmlPullParser from which to read the list data.
     * @param endTag Name of the tag that will end the list, usually "list".
     * @param name An array of one string, used to return the name attribute
     *             of the list's tag.
     * 
     * @return HashMap The newly generated list.
     * 
     * @see #readListXml
     */
    public static final ArrayList readThisListXml(XmlPullParser parser, String endTag, String[] name)
    throws XmlPullParserException, java.io.IOException
    {
        ArrayList list = new ArrayList();

        int eventType = parser.getEventType();
        do {
            if (eventType == parser.START_TAG) {
                Object val = readThisValueXml(parser, name);
                list.add(val);
                //System.out.println("Adding to list: " + val);
            } else if (eventType == parser.END_TAG) {
                if (parser.getName().equals(endTag)) {
                    return list;
                }
                throw new XmlPullParserException(
                    "Expected " + endTag + " end tag at: " + parser.getName());
            }
            eventType = parser.next();
        } while (eventType != parser.END_DOCUMENT);

        throw new XmlPullParserException(
            "Document ended before " + endTag + " end tag");
    }

    /**
     * Read an int[] object from an XmlPullParser.  The XML data could
     * previously have been generated by writeIntArrayXml().  The XmlPullParser
     * must be positioned <em>after</em> the tag that begins the list.
     * 
     * @param parser The XmlPullParser from which to read the list data.
     * @param endTag Name of the tag that will end the list, usually "list".
     * @param name An array of one string, used to return the name attribute
     *             of the list's tag.
     * 
     * @return Returns a newly generated int[].
     * 
     * @see #readListXml
     */
    public static final int[] readThisIntArrayXml(XmlPullParser parser,
            String endTag, String[] name)
            throws XmlPullParserException, java.io.IOException {
        
        int num;
        try {
            num = Integer.parseInt(parser.getAttributeValue(null, "num"));
        } catch (NullPointerException e) {
            throw new XmlPullParserException(
                    "Need num attribute in byte-array");
        } catch (NumberFormatException e) {
            throw new XmlPullParserException(
                    "Not a number in num attribute in byte-array");
        }
        
        int[] array = new int[num];
        int i = 0;

        int eventType = parser.getEventType();
        do {
            if (eventType == parser.START_TAG) {
                if (parser.getName().equals("item")) {
                    try {
                        array[i] = Integer.parseInt(
                                parser.getAttributeValue(null, "value"));
                    } catch (NullPointerException e) {
                        throw new XmlPullParserException(
                                "Need value attribute in item");
                    } catch (NumberFormatException e) {
                        throw new XmlPullParserException(
                                "Not a number in value attribute in item");
                    }                    
                } else {
                    throw new XmlPullParserException(
                            "Expected item tag at: " + parser.getName());
                }
            } else if (eventType == parser.END_TAG) {
                if (parser.getName().equals(endTag)) {
                    return array;
                } else if (parser.getName().equals("item")) {
                    i++;
                } else {
                    throw new XmlPullParserException(
                        "Expected " + endTag + " end tag at: "
                        + parser.getName());
                }
            }
            eventType = parser.next();
        } while (eventType != parser.END_DOCUMENT);

        throw new XmlPullParserException(
            "Document ended before " + endTag + " end tag");
    }

    /**
     * Read a flattened object from an XmlPullParser.  The XML data could
     * previously have been written with writeMapXml(), writeListXml(), or
     * writeValueXml().  The XmlPullParser must be positioned <em>at</em> the
     * tag that defines the value.
     * 
     * @param parser The XmlPullParser from which to read the object.
     * @param name An array of one string, used to return the name attribute
     *             of the value's tag.
     * 
     * @return Object The newly generated value object.
     * 
     * @see #readMapXml
     * @see #readListXml
     * @see #writeValueXml
     */
    public static final Object readValueXml(XmlPullParser parser, String[] name)
    throws XmlPullParserException, java.io.IOException
    {
        int eventType = parser.getEventType();
        do {
            if (eventType == parser.START_TAG) {
                return readThisValueXml(parser, name);
            } else if (eventType == parser.END_TAG) {
                throw new XmlPullParserException(
                    "Unexpected end tag at: " + parser.getName());
            } else if (eventType == parser.TEXT) {
                throw new XmlPullParserException(
                    "Unexpected text: " + parser.getText());
            }
            eventType = parser.next();
        } while (eventType != parser.END_DOCUMENT);

        throw new XmlPullParserException(
            "Unexpected end of document");
    }

    private static final Object readThisValueXml(XmlPullParser parser, String[] name)
    throws XmlPullParserException, java.io.IOException
    {
        final String valueName = parser.getAttributeValue(null, "name");
        final String tagName = parser.getName();

        //System.out.println("Reading this value tag: " + tagName + ", name=" + valueName);

        Object res;

        if (tagName.equals("null")) {
            res = null;
        } else if (tagName.equals("string")) {
            String value = "";
            int eventType;
            while ((eventType = parser.next()) != parser.END_DOCUMENT) {
                if (eventType == parser.END_TAG) {
                    if (parser.getName().equals("string")) {
                        name[0] = valueName;
                        //System.out.println("Returning value for " + valueName + ": " + value);
                        return value;
                    }
                    throw new XmlPullParserException(
                        "Unexpected end tag in <string>: " + parser.getName());
                } else if (eventType == parser.TEXT) {
                    value += parser.getText();
                } else if (eventType == parser.START_TAG) {
                    throw new XmlPullParserException(
                        "Unexpected start tag in <string>: " + parser.getName());
                }
            }
            throw new XmlPullParserException(
                "Unexpected end of document in <string>");
        } else if (tagName.equals("int")) {
            res = Integer.parseInt(parser.getAttributeValue(null, "value"));
        } else if (tagName.equals("long")) {
            res = Long.valueOf(parser.getAttributeValue(null, "value"));
        } else if (tagName.equals("float")) {
            res = new Float(parser.getAttributeValue(null, "value"));
        } else if (tagName.equals("double")) {
            res = new Double(parser.getAttributeValue(null, "value"));
        } else if (tagName.equals("boolean")) {
            res = Boolean.valueOf(parser.getAttributeValue(null, "value"));
        } else if (tagName.equals("int-array")) {
            parser.next();
            res = readThisIntArrayXml(parser, "int-array", name);
            name[0] = valueName;
            //System.out.println("Returning value for " + valueName + ": " + res);
            return res;
        } else if (tagName.equals("map")) {
            parser.next();
            res = readThisMapXml(parser, "map", name);
            name[0] = valueName;
            //System.out.println("Returning value for " + valueName + ": " + res);
            return res;
        } else if (tagName.equals("list")) {
            parser.next();
            res = readThisListXml(parser, "list", name);
            name[0] = valueName;
            //System.out.println("Returning value for " + valueName + ": " + res);
            return res;
        } else {
            throw new XmlPullParserException(
                "Unknown tag: " + tagName);
        }

        // Skip through to end tag.
        int eventType;
        while ((eventType = parser.next()) != parser.END_DOCUMENT) {
            if (eventType == parser.END_TAG) {
                if (parser.getName().equals(tagName)) {
                    name[0] = valueName;
                    //System.out.println("Returning value for " + valueName + ": " + res);
                    return res;
                }
                throw new XmlPullParserException(
                    "Unexpected end tag in <" + tagName + ">: " + parser.getName());
            } else if (eventType == parser.TEXT) {
                throw new XmlPullParserException(
                "Unexpected text in <" + tagName + ">: " + parser.getName());
            } else if (eventType == parser.START_TAG) {
                throw new XmlPullParserException(
                    "Unexpected start tag in <" + tagName + ">: " + parser.getName());
            }
        }
        throw new XmlPullParserException(
            "Unexpected end of document in <" + tagName + ">");
    }

    public static final void beginDocument(XmlPullParser parser, String firstElementName) throws XmlPullParserException, IOException
    {
        int type;
        while ((type=parser.next()) != parser.START_TAG
                   && type != parser.END_DOCUMENT) {
            ;
        }

        if (type != parser.START_TAG) {
            throw new XmlPullParserException("No start tag found");
        }
        
        if (!parser.getName().equals(firstElementName)) {
            throw new XmlPullParserException("Unexpected start tag: found " + parser.getName() +
                    ", expected " + firstElementName);
        }
    }
    
    public static final void nextElement(XmlPullParser parser) throws XmlPullParserException, IOException
    {
        int type;
        while ((type=parser.next()) != parser.START_TAG
                   && type != parser.END_DOCUMENT) {
            ;
        }   
    }
}