swing text heml parse error

[Chao Liu]

Hello: I got  a Technology tips about "Extracting Links from an HTML File" from sun website.   It is very short I attached it to this email. It is very useful to some simple html files. But I meet errors when I use this class to extracct links from some html files. erro: Exception in thread "main" java.lang.NoClassDefFoundError         at java.lang.Class.forName0(Native Method)         at java.lang.Class.forName(Class.java:120)         at java.awt.Toolkit$2.run(Toolkit.java:498)         at java.security.AccessController.doPrivileged(Native Method)         at java.awt.Toolkit.getDefaultToolkit(Toolkit.java:489)         at javax.swing.text.html.CSS.getValidFontNameMapping(CSS.java:932)         at javax.swing.text.html.CSS$FontFamily.parseCssValue(CSS.java:1789)         at javax.swing.text.html.CSS.getInternalCSSValue(CSS.java:531)         at javax.swing.text.html.CSS.addInternalCSSValue(CSS.java:516)         at javax.swing.text.html.StyleSheet.addCSSAttribute(StyleSheet.java:436)         at javax.swing.text.html.StyleSheet$CssParser.handleValue(StyleSheet.java:3252)         at javax.swing.text.html.CSSParser.parseDeclaration(CSSParser.java:340)         at javax.swing.text.html.CSSParser.parseDeclarationBlock(CSSParser.java:307)         at javax.swing.text.html.CSSParser.parseRuleSet(CSSParser.java:254)         at javax.swing.text.html.CSSParser.getNextStatement(CSSParser.java:160)         at javax.swing.text.html.CSSParser.parse(CSSParser.java:135)         at javax.swing.text.html.StyleSheet$CssParser.parse(StyleSheet.java:3190)         at javax.swing.text.html.StyleSheet.addRule(StyleSheet.java:245)         at javax.swing.text.html.HTMLDocument$HTMLReader.addCSSRules(HTMLDocument.java:308 4)         at javax.swing.text.html.HTMLDocument$HTMLReader$HeadAction.end(HTMLDocument.java: 2276) at javax.swing.text.html.HTMLDocument$HTMLReader.handleEndTag(HTMLDocument.java:20 40)         at javax.swing.text.html.parser.DocumentParser.handleEndTag(DocumentParser.java:22 0)         at javax.swing.text.html.parser.Parser.parse(Parser.java:2005)         at javax.swing.text.html.parser.DocumentParser.parse(DocumentParser.java:109)         at javax.swing.text.html.parser.ParserDelegator.parse(ParserDelegator.java:74)         at javax.swing.text.html.HTMLEditorKit.read(HTMLEditorKit.java:239)         at GetLinks.main(GetLinks.java:22)   Chao Liu 2001.4.28