olá pessoal,
depois de usar o generate javadoc do menu project, deu esse erro ai embaixo, o que eu fiz de errado? 
o código funciona perfeitamente !
o arquivo html é gerado com 0 bytes
Loading source file C:\JAVA\Programas\Relacional\Relacional.java…
Constructing Javadoc information…
Standard Doclet version 1.6.0_24
Building tree for all the packages and classes…
Generating C:\JAVA\Programas\Relacional\doc\Relacional.html…
java.lang.IllegalArgumentException
at sun.net.www.ParseUtil.decode(ParseUtil.java:189)
at sun.misc.URLClassPath$FileLoader.(URLClassPath.java:958)
at sun.misc.URLClassPath$3.run(URLClassPath.java:328)
at java.security.AccessController.doPrivileged(Native Method)
at sun.misc.URLClassPath.getLoader(URLClassPath.java:322)
at sun.misc.URLClassPath.getLoader(URLClassPath.java:299)
at sun.misc.URLClassPath.findResource(URLClassPath.java:145)
at java.net.URLClassLoader$2.run(URLClassLoader.java:385)
at java.security.AccessController.doPrivileged(Native Method)
at java.net.URLClassLoader.findResource(URLClassLoader.java:382)
at java.lang.ClassLoader.getResource(ClassLoader.java:1003)
at java.lang.ClassLoader.getResourceAsStream(ClassLoader.java:1193)
at javax.xml.parsers.SecuritySupport$4.run(SecuritySupport.java:96)
at java.security.AccessController.doPrivileged(Native Method)
at javax.xml.parsers.SecuritySupport.getResourceAsStream(SecuritySupport.java:89)
at javax.xml.parsers.FactoryFinder.findJarServiceProvider(FactoryFinder.java:250)
at javax.xml.parsers.FactoryFinder.find(FactoryFinder.java:223)
at javax.xml.parsers.SAXParserFactory.newInstance(SAXParserFactory.java:128)
at com.sun.tools.doclets.internal.toolkit.builders.LayoutParser.parseXML(LayoutParser.java:72)
at com.sun.tools.doclets.internal.toolkit.builders.ClassBuilder.build(ClassBuilder.java:108)
at com.sun.tools.doclets.formats.html.HtmlDoclet.generateClassFiles(HtmlDoclet.java:155)
at com.sun.tools.doclets.internal.toolkit.AbstractDoclet.generateClassFiles(AbstractDoclet.java:177)
at com.sun.tools.doclets.internal.toolkit.AbstractDoclet.generateClassFiles(AbstractDoclet.java:161)
at com.sun.tools.doclets.internal.toolkit.AbstractDoclet.startGeneration(AbstractDoclet.java:106)
at com.sun.tools.doclets.internal.toolkit.AbstractDoclet.start(AbstractDoclet.java:64)
at com.sun.tools.doclets.formats.html.HtmlDoclet.start(HtmlDoclet.java:42)
at com.sun.tools.doclets.standard.Standard.start(Standard.java:23)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:597)
at com.sun.tools.javadoc.DocletInvoker.invoke(DocletInvoker.java:269)
at com.sun.tools.javadoc.DocletInvoker.start(DocletInvoker.java:143)
at com.sun.tools.javadoc.Start.parseAndExecute(Start.java:340)
at com.sun.tools.javadoc.Start.begin(Start.java:128)
at com.sun.tools.javadoc.Main.execute(Main.java:41)
at com.sun.tools.javadoc.Main.main(Main.java:31)
com.sun.tools.doclets.internal.toolkit.util.DocletAbortException
at com.sun.tools.doclets.internal.toolkit.builders.LayoutParser.parseXML(LayoutParser.java:79)
at com.sun.tools.doclets.internal.toolkit.builders.ClassBuilder.build(ClassBuilder.java:108)
at com.sun.tools.doclets.formats.html.HtmlDoclet.generateClassFiles(HtmlDoclet.java:155)
at com.sun.tools.doclets.internal.toolkit.AbstractDoclet.generateClassFiles(AbstractDoclet.java:177)
at com.sun.tools.doclets.internal.toolkit.AbstractDoclet.generateClassFiles(AbstractDoclet.java:161)
at com.sun.tools.doclets.internal.toolkit.AbstractDoclet.startGeneration(AbstractDoclet.java:106)
at com.sun.tools.doclets.internal.toolkit.AbstractDoclet.start(AbstractDoclet.java:64)
at com.sun.tools.doclets.formats.html.HtmlDoclet.start(HtmlDoclet.java:42)
at com.sun.tools.doclets.standard.Standard.start(Standard.java:23)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:597)
at com.sun.tools.javadoc.DocletInvoker.invoke(DocletInvoker.java:269)
at com.sun.tools.javadoc.DocletInvoker.start(DocletInvoker.java:143)
at com.sun.tools.javadoc.Start.parseAndExecute(Start.java:340)
at com.sun.tools.javadoc.Start.begin(Start.java:128)
at com.sun.tools.javadoc.Main.execute(Main.java:41)
at com.sun.tools.javadoc.Main.main(Main.java:31)
com.sun.tools.doclets.internal.toolkit.util.DocletAbortException
at com.sun.tools.doclets.formats.html.HtmlDoclet.generateClassFiles(HtmlDoclet.java:159)
at com.sun.tools.doclets.internal.toolkit.AbstractDoclet.generateClassFiles(AbstractDoclet.java:177)
at com.sun.tools.doclets.internal.toolkit.AbstractDoclet.generateClassFiles(AbstractDoclet.java:161)
at com.sun.tools.doclets.internal.toolkit.AbstractDoclet.startGeneration(AbstractDoclet.java:106)
at com.sun.tools.doclets.internal.toolkit.AbstractDoclet.start(AbstractDoclet.java:64)
at com.sun.tools.doclets.formats.html.HtmlDoclet.start(HtmlDoclet.java:42)
at com.sun.tools.doclets.standard.Standard.start(Standard.java:23)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:597)
at com.sun.tools.javadoc.DocletInvoker.invoke(DocletInvoker.java:269)
at com.sun.tools.javadoc.DocletInvoker.start(DocletInvoker.java:143)
at com.sun.tools.javadoc.Start.parseAndExecute(Start.java:340)
at com.sun.tools.javadoc.Start.begin(Start.java:128)
at com.sun.tools.javadoc.Main.execute(Main.java:41)
at com.sun.tools.javadoc.Main.main(Main.java:31)