Java tutorial
//package com.java2s; /* * Copyright (C) 2006 The Android Open Source Project * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ import java.util.ArrayList; import java.util.HashMap; import org.xmlpull.v1.XmlPullParser; import org.xmlpull.v1.XmlPullParserException; public class Main { /** * 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 + ">"); } /** * 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 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"); } }