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1 package prefuse.data.io;
2
3 import java.io.InputStream  ;
4 import java.util.Date ;
5
6 import javax.xml.parsers.SAXParser ;
7 import javax.xml.parsers.SAXParserFactory ;
8
9 import org.xml.sax.Attributes ;
10 import org.xml.sax.helpers.DefaultHandler ;
11
12 import prefuse.data.Graph;
13 import prefuse.data.Node;
14 import prefuse.data.Table;
15 import prefuse.data.Tree;
16 import prefuse.data.parser.DataParseException;
17 import prefuse.data.parser.DataParser;
18 import prefuse.data.parser.ParserFactory;
19
20
21
31 public class TreeMLReader extends AbstractGraphReader {
32
33 private ParserFactory m_pf = ParserFactory.getDefaultFactory();
34
35
38 public Graph readGraph(InputStream is) throws DataIOException {
39 try {
40 TreeMLHandler handler = new TreeMLHandler();
41 SAXParserFactory factory = SAXParserFactory.newInstance();
42 SAXParser saxParser = factory.newSAXParser();
43 saxParser.parse(is, handler);
44 return handler.getTree();
45 } catch ( Exception e ) {
46 throw new DataIOException(e);
47 }
48 }
49
50
53 public static interface Tokens {
54 public static final String TREE = "tree";
55 public static final String BRANCH = "branch";
56 public static final String LEAF = "leaf";
57 public static final String ATTR = "attribute";
58 public static final String NAME = "name";
59 public static final String VALUE = "value";
60 public static final String TYPE = "type";
61
62 public static final String DECLS = "declarations";
63 public static final String DECL = "attributeDecl";
64
65 public static final String INT = "Int";
66 public static final String INTEGER = "Integer";
67 public static final String LONG = "Long";
68 public static final String FLOAT = "Float";
69 public static final String REAL = "Real";
70 public static final String STRING = "String";
71 public static final String DATE = "Date";
72 public static final String CATEGORY = "Category";
73
74 public static final String BOOLEAN = "Boolean";
76 public static final String DOUBLE = "Double";
77 }
78
79
82 public class TreeMLHandler extends DefaultHandler implements Tokens {
83
84 private Table m_nodes = null;
85 private Tree m_tree = null;
86
87 private Node m_activeNode = null;
88 private boolean m_inSchema = true;
89
90 public void startDocument() {
91 m_tree = new Tree();
92 m_nodes = m_tree.getNodeTable();
93 }
94
95 private void schemaCheck() {
96 if ( m_inSchema ) {
97 m_inSchema = false;
98 }
99 }
100
101 public void endElement(String namespaceURI, String localName, String qName) {
102 if ( qName.equals(BRANCH) || qName.equals(LEAF) ) {
103 m_activeNode = m_activeNode.getParent();
104 }
105 }
106
107 public void startElement(String namespaceURI, String localName,
108 String qName, Attributes atts) {
109 if ( qName.equals(DECL) ) {
110 if ( !m_inSchema ) {
111 throw new RuntimeException ("All declarations must be done "
112 + "before nodes begin");
113 }
114 String name = atts.getValue(NAME);
115 String type = atts.getValue(TYPE);
116 Class t = parseType(type);
117 m_nodes.addColumn(name, t);
118 }
119 else if ( qName.equals(BRANCH) || qName.equals(LEAF) ) {
120 schemaCheck();
121
122 Node n;
124 if ( m_activeNode == null ) {
125 n = m_tree.addRoot();
126 } else {
127 n = m_tree.addChild(m_activeNode);
128 }
129 m_activeNode = n;
130 }
131 else if ( qName.equals(ATTR) ) {
132 parseAttribute(atts);
134 }
135 }
136
137 protected void parseAttribute(Attributes atts) {
138 String alName, name = null, value = null;
139 for ( int i = 0; i < atts.getLength(); i++ ) {
140 alName = atts.getQName(i);
141 if ( alName.equals(NAME) ) {
142 name = atts.getValue(i);
143 } else if ( alName.equals(VALUE) ) {
144 value = atts.getValue(i);
145 }
146 }
147 if ( name == null || value == null ) {
148 System.err.println("Attribute under-specified");
149 return;
150 }
151
152 try {
153 Object val = parse(value, m_nodes.getColumnType(name));
154 m_activeNode.set(name, val);
155 } catch ( Exception e ) {
156 throw new RuntimeException (e);
157 }
158 }
159
160 protected Object parse(String s, Class type)
161 throws DataParseException
162 {
163 DataParser dp = m_pf.getParser(type);
164 return dp.parse(s);
165 }
166
167 protected Class parseType(String type) {
168 type = Character.toUpperCase(type.charAt(0)) +
169 type.substring(1).toLowerCase();
170 if ( type.equals(INT) || type.equals(INTEGER) ) {
171 return int.class;
172 } else if ( type.equals(LONG) ) {
173 return long.class;
174 } else if ( type.equals(FLOAT) ) {
175 return float.class;
176 } else if ( type.equals(DOUBLE) || type.equals(REAL)) {
177 return double.class;
178 } else if ( type.equals(BOOLEAN) ) {
179 return boolean.class;
180 } else if ( type.equals(STRING) ) {
181 return String .class;
182 } else if ( type.equals(DATE) ) {
183 return Date .class;
184 } else {
185 throw new RuntimeException ("Unrecognized data type: "+type);
186 }
187 }
188
189 public Tree getTree() {
190 return m_tree;
191 }
192
193 }
195 } |
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