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diff --git a/subsonic-main/src/main/java/net/sourceforge/subsonic/util/XMLBuilder.java b/subsonic-main/src/main/java/net/sourceforge/subsonic/util/XMLBuilder.java
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+/*
+ This file is part of Subsonic.
+
+ Subsonic is free software: you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation, either version 3 of the License, or
+ (at your option) any later version.
+
+ Subsonic is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with Subsonic.  If not, see <http://www.gnu.org/licenses/>.
+
+ Copyright 2009 (C) Sindre Mehus
+ */
+package net.sourceforge.subsonic.util;
+
+import org.apache.commons.lang.StringEscapeUtils;
+import org.json.JSONException;
+import org.json.JSONObject;
+import org.json.XML;
+
+import java.io.IOException;
+import java.io.StringWriter;
+import java.io.Writer;
+import java.util.Arrays;
+import java.util.Collections;
+import java.util.Iterator;
+import java.util.LinkedHashMap;
+import java.util.Map;
+import java.util.Stack;
+
+
+/**
+ * Simplifies building of XML documents.
+ * <p/>
+ * <b>Example:</b><br/>
+ * The following code:
+ * <pre>
+ * XMLBuilder builder = XMLBuilder.createXMLBuilder();
+ * builder.add("foo").add("bar");
+ * builder.add("zonk", 42);
+ * builder.end().end();
+ * System.out.println(builder.toString());
+ * </pre>
+ * produces the following XML:
+ * <pre>
+ * &lt;foo&gt;
+ *   &lt;bar&gt;
+ *     &lt;zonk&gt;42&lt;/zonk&gt;
+ *   &lt;/bar&gt;
+ * &lt;/foo&gt;
+ * </pre>
+ * This class is <em>not</em> thread safe.
+ * <p/>
+ * Also supports JSON and JSONP formats.
+ *
+ * @author Sindre Mehus
+ */
+public class XMLBuilder {
+
+    private static final String INDENTATION = "  ";
+    private static final String NEWLINE = "\n";
+
+    private final Writer writer = new StringWriter();
+    private final Stack<String> elementStack = new Stack<String>();
+    private final boolean json;
+    private final String jsonpCallback;
+
+    public static XMLBuilder createXMLBuilder() {
+        return new XMLBuilder(false, null);
+    }
+
+    public static XMLBuilder createJSONBuilder() {
+        return new XMLBuilder(true, null);
+    }
+
+    public static XMLBuilder createJSONPBuilder(String callback) {
+        return new XMLBuilder(true, callback);
+    }
+
+    /**
+     * Creates a new instance.
+     *
+     * @param json          Whether to produce JSON rather than XML.
+     * @param jsonpCallback Name of javascript callback for JSONP.
+     */
+    private XMLBuilder(boolean json, String jsonpCallback) {
+        this.json = json;
+        this.jsonpCallback = jsonpCallback;
+    }
+
+    /**
+     * Adds an XML preamble, with the given encoding. The preamble will typically
+     * look like this:
+     * <p/>
+     * <code>&lt;?xml version="1.0" encoding="UTF-8"?&gt;</code>
+     *
+     * @param encoding The encoding to put in the preamble.
+     * @return A reference to this object.
+     */
+    public XMLBuilder preamble(String encoding) throws IOException {
+        writer.write("<?xml version=\"1.0\" encoding=\"");
+        writer.write(encoding);
+        writer.write("\"?>");
+        newline();
+        return this;
+    }
+
+    /**
+     * Adds an element with the given name and a single attribute.
+     *
+     * @param element        The element name.
+     * @param attributeKey   The attributes key.
+     * @param attributeValue The attributes value.
+     * @param close          Whether to close the element.
+     * @return A reference to this object.
+     */
+    public XMLBuilder add(String element, String attributeKey, Object attributeValue, boolean close) throws IOException {
+        return add(element, close, new Attribute(attributeKey, attributeValue));
+    }
+
+    /**
+     * Adds an element with the given name and attributes.
+     *
+     * @param element    The element name.
+     * @param close      Whether to close the element.
+     * @param attributes The element attributes.
+     * @return A reference to this object.
+     */
+    public XMLBuilder add(String element, boolean close, Attribute... attributes) throws IOException {
+        return add(element, Arrays.asList(attributes), close);
+    }
+
+    /**
+     * Adds an element with the given name and attributes.
+     *
+     * @param element    The element name.
+     * @param attributes The element attributes.
+     * @param close      Whether to close the element.
+     * @return A reference to this object.
+     */
+    public XMLBuilder add(String element, Iterable<Attribute> attributes, boolean close) throws IOException {
+        return add(element, attributes, null, close);
+    }
+
+    /**
+     * Adds an element with the given name, attributes and character data.
+     *
+     * @param element    The element name.
+     * @param attributes The element attributes.
+     * @param text       The character data.
+     * @param close      Whether to close the element.
+     * @return A reference to this object.
+     */
+    public XMLBuilder add(String element, Iterable<Attribute> attributes, String text, boolean close) throws IOException {
+        indent();
+        elementStack.push(element);
+        writer.write('<');
+        writer.write(element);
+
+        if (attributes == null) {
+            attributes = Collections.emptyList();
+        }
+
+        Iterator<Attribute> iterator = attributes.iterator();
+
+        if (iterator.hasNext()) {
+            writer.write(' ');
+        }
+        while (iterator.hasNext()) {
+            Attribute attribute = iterator.next();
+            attribute.append(writer);
+            if (iterator.hasNext()) {
+                writer.write(' ');
+            }
+        }
+
+        if (close && text == null) {
+            elementStack.pop();
+            writer.write("/>");
+        } else {
+            writer.write('>');
+        }
+
+        if (text != null) {
+            writer.write(text);
+
+            if (close) {
+                elementStack.pop();
+                writer.write("</");
+                writer.write(element);
+                writer.write('>');
+            }
+        }
+
+        newline();
+        return this;
+    }
+
+    /**
+     * Closes the current element.
+     *
+     * @return A reference to this object.
+     * @throws IllegalStateException If there are no unclosed elements.
+     */
+    public XMLBuilder end() throws IllegalStateException, IOException {
+        if (elementStack.isEmpty()) {
+            throw new IllegalStateException("There are no unclosed elements.");
+        }
+
+        String element = elementStack.pop();
+        indent();
+        writer.write("</");
+        writer.write(element);
+        writer.write('>');
+        newline();
+        return this;
+    }
+
+    /**
+     * Closes all unclosed elements.
+     *
+     * @return A reference to this object.
+     */
+    public XMLBuilder endAll() throws IOException {
+        while (!elementStack.isEmpty()) {
+            end();
+        }
+        return this;
+    }
+
+    /**
+     * Returns the XML document as a string.
+     */
+    @Override
+    public String toString() {
+        String xml = writer.toString();
+        if (!json) {
+            return xml;
+        }
+        try {
+            JSONObject jsonObject = XML.toJSONObject(xml);
+
+            if (jsonpCallback != null) {
+                return jsonpCallback + "(" + jsonObject.toString(1) + ");";
+            }
+
+            return jsonObject.toString(1);
+        } catch (JSONException x) {
+            throw new RuntimeException("Failed to convert from XML to JSON.", x);
+        }
+    }
+
+    private void indent() throws IOException {
+        int depth = elementStack.size();
+        for (int i = 0; i < depth; i++) {
+            writer.write(INDENTATION);
+        }
+    }
+
+    private void newline() throws IOException {
+        writer.write(NEWLINE);
+    }
+
+    /**
+     * An XML element attribute.
+     */
+    public static class Attribute {
+
+        private final String key;
+        private final Object value;
+
+        public Attribute(String key, Object value) {
+            this.key = key;
+            this.value = value;
+        }
+
+        public String getKey() {
+            return key;
+        }
+
+        public Object getValue() {
+            return value;
+        }
+
+        private void append(Writer writer) throws IOException {
+            if (key != null && value != null) {
+                writer.write(key);
+                writer.write("=\"");
+                writer.write(StringEscapeUtils.escapeXml(value.toString()));
+                writer.write("\"");
+            }
+        }
+    }
+
+    /**
+     * A set of attributes.
+     */
+    public static class AttributeSet implements Iterable<Attribute> {
+
+        private final Map<String, Attribute> attributes = new LinkedHashMap<String, Attribute>();
+
+        public void add(Attribute attribute) {
+            attributes.put(attribute.getKey(), attribute);
+        }
+
+        public void add(String key, Object value) {
+            if (key != null && value != null) {
+                add(new Attribute(key, value));
+            }
+        }
+
+        public void addAll(Iterable<Attribute> attributes) {
+            for (Attribute attribute : attributes) {
+                add(attribute);
+            }
+        }
+
+        public Iterator<Attribute> iterator() {
+            return attributes.values().iterator();
+        }
+    }
+
+}