GWT client development can be done simply with the original NetBeans IDE, without the special GWT4NB add-on. The add-on is more for development involving the server side. As a client-only GWT tool, it improves the development productivity greatly.
The setup is all documented in this README file on github:
Files: gwt-linux-1.7.1.tar.bz2 https://developers.google.com/web-toolkit/versions Install ========== JDK and NetBeans Installed in $HOME/bin/jdk1.6.0_25 and $HOME/bin/netbeans. Will use the ant coming with NetBeans. Set .bash_profile: JAVA_HOME=$HOME/bin/jdk1.6.0_25 export JAVA_HOME ANT_HOME=$HOME/bin/netbeans/java/ant export ANT_HOME PATH=$JAVA_HOME/bin:$PATH PATH=$ANT_HOME/bin:$PATH export PATH On Fedora 14, install compat-libstdc++-33 for the hosted mode to work. Run Example Hello ================== cd work/gwt-linux-1.7.1/samples/Hello ant hosted Run Example Hello Out-of-the-tree ================================== cd work mkdir build cp -a gwt-linux-1.7.1/samples/Hello ./build cd build/Hello Edit build.xml to change gwt.sdk pointing to ../../gwt-linux-1.7.1 ant hosted Run Example Hello Out-of-the-tree in NetBeans ============================================== Create a java project with existing code using the same work/Hello directory for the project. Netbeans will add two files to Hello directory. Ignore them. Use file window in Netbeans, right click on build.xml node, and run build or hosted target. The ant inside Netbeans will just build everything as if you are doing it from command line. To have the sample Hello to build please add the gwt-user.jar to the library. To have the sample Showcase to build please add also gwt-dev-<os>.jar, because the java code need to generate also the source code into the HTML pages. Run on Windows 64bit ====================== Install JDK 64bit. Install Netbeans JavaSE. Install JRE 32bit. Edit build.xml:  "gwt.sdk" same as mentioned above.  Change the target "java" under "hosted" to have an extra value for property jvm: jvm="C:\\Users\\whoami\\Programs\\jre6.32\\bin\\java". The path is the jre 32bit installation. Debug with Java Debugger ========================= Refer to page 96 of "Beginning Google Web Toolkit From Novice to Professional" by Bram Smeets, Uri Boness, and Ronald Bankras Apress, 2008 java -Xdebug \ -Xrunjdmp:transport-dt_socket,address=127.0.0.1:52996,suspend=y,server=n \ -cp "$APPDIR/src:$APPDIR/bin:$GWT_HOME/gwt-user.jar:$GWT_HOME/gwt-dev-linux.jar" \ com.google.gwt.dev.GWTShell -out "$APPDIR/www" "$@" \ com.abc.gwt.GWTasks/GWTasks.html Options for Hosted Mode ========================= java -cp gwt-dev-<your platform here>.jar com.google.gwt.dev.HostedMode Missing required argument 'module[s]' Google Web Toolkit 1.7.0 HostedMode [-noserver] [-port port-number | "auto"] [-whitelist whitelist-string] [-blacklist blacklist-string] [-logLevel level] [-gen dir] [-style style] [-ea] [-server servletContainerLauncher] [-startupUrl url] [-war dir] [-extra dir] [-workDir dir] [-localWorkers count] module[s] where -noserver Prevents the embedded web server from running -port Specifies the TCP port for the embedded web server (defaults to 8888) -whitelist Allows the user to browse URLs that match the specified regexes (comma or space separated) -blacklist Prevents the user browsing URLs that match the specified regexes (comma or space separated) -logLevel The level of logging detail: ERROR, WARN, INFO, TRACE, DEBUG, SPAM, or ALL -gen The directory into which generated files will be written for review -style Script output style: OBF[USCATED], PRETTY, or DETAILED (defaults to OBF) -ea Debugging: causes the compiled output to check assert statements. -server Specifies a different embedded web server to run (must implement ServletContainerLauncher) -startupUrl Automatically launches the specified URL -war The war directory to write output files into (defaults to war) -extra The directory into which extra, non-deployed files will be written -workDir The compiler work directory (must be writeable; defaults to a system temp dir) -localWorkers Specifies the number of local workers to use when compiling permutations and module[s] Specifies the name(s) of the module(s) to host