CleverGWT

From PlcWiki

Contents 1 Installation Steps 2 Resources 3 Unified look of the Clever System applications with AppEntryPoint 3.1 Založení projektu 3.2 Java Build Path 3.3 AppEntryPoint 3.4 Interface Service a ServiceAsync 3.5 Serverová strana - ServiceImpl 4 ClvListGrid - Extension of ListGrid 5 SecuredServiceServlet 6 JettyLauncher 7 DocumentServlet and UploadServlet 8 StringUtil 9 ParserCSV 10 BCrypt 11 String Externalizer (i18n)

Installation Steps

• Repository: svn+ssh://username@oko.clever.cz
• Path: /java/CleverGWT
• Entry-point descriptor ...gwt.xml:

 <inherits name="cz.clever.gwt.ext.Module" />

• Don't forget to check your current version of the GWT

Resources

Resources are located in folder src/cz/clever/gwt/ext/public.

Example of icon usage:

 logoutBtn.setIcon(Resource.Util.getIconPath("door_out")); //$NON-NLS-1$

Unified look of the Clever System applications with AppEntryPoint

AppEntryPoint is an implementation of the EntryPoint interface.

Additionally steps: splash screen, sounds and icons. Images and icons are in CleverGWT/src/cz/clever/gwt/ext/public/images.

Založení projektu

Vybrat: Google/Web Application Project. Package: cz.clever.nazevaplikace.gwt. GWT 2.4.0

Java Build Path

Projects - CleverGWT

Libraries - CleverGWT/lib/smartgwt-skins.jar, CleverGWT/lib/smartgwt.jar, CleverGWT/lib/log4j.jar

AppEntryPoint

Vymyslet jméno aplikace getAppName() a implementaci:

 public void drawContent(String initData, DataCallback<com.smartgwt.client.widgets.Canvas> callback) { callback.execute(new Canvas()); }

Interface Service a ServiceAsync

 @RemoteServiceRelativePath("service")
 public interface Service extends RemoteService, ServiceCore { }

Serverová strana - ServiceImpl

 public class ServiceImpl extends SecuredServiceServlet implements Service {
 
	@Override
	protected String getAppName() {
		return "myAppName";// security role-name
	}
 
	@Override
	protected KeyValueString getUserName() {
		return new KeyValueString() {
 
			@Override
			public String getKey() {return "user-data-key";}
 
			@Override
			public String getValue() {return "guest";}
 
			@Override
			public void setValue(String value) {}
 
		};
	}
 }

ClvListGrid - Extension of ListGrid

Simplification of CRUD usage:

ListGrid grid = new ClvListGrid(new ClvListGrid.Delegate() {
 
			@Override
			public void executeUpdate(ClvListGridResponse response) {
				// Map<String, Object> reqMap = response.getRequestMap();
				// response.response(...
			}
 
			@Override
			public void executeRemove(ClvListGridResponse response) {}
 
			@Override
			public void executeFetch(ClvListGridResponse response) {}
 
			@Override
			public void executeAdd(ClvListGridResponse response) {}
 
			@Override
			public DataSourceField[] createFields() {
				return new DataSourceField[] { new DataSourceTextField("Field Name") };
			}
		});

Note: If you are implementing executeRemove/Add/Fetch you must call response.response(...). Not in executeUpdate.

Real-time data synchronization (only works with URL parameter "im"):

 grid = new ClvListGrid(delegate, "MySubscribeId");

SecuredServiceServlet

Benefits:

• Request without GWT permutation header will be blocked (potential CSRF attack)
• Authorization check before the servlet methods are called from client (methods must be annotated as Secured)

 public class MyGWTServiceImpl extends SecuredServiceServlet implements ...
 
 @Override
 protected boolean isInRole(String user, String method, Object value, Integer position) {
		// check for permission
 }

JettyLauncher

Allow you to set custom logging and configuration.

Example of startup arguments:

-startupUrl Entrypoint.html ... -server cz.clever.gwt.ext.server.JettyLauncher  ...

Inside a class:

 wac.setConfigurationClasses(new String[] { 
        "org.mortbay.jetty.webapp.WebInfConfiguration", 
        "org.mortbay.jetty.plus.webapp.EnvConfiguration",//jetty-env 
        "org.mortbay.jetty.plus.webapp.Configuration", //web.xml 
        "org.mortbay.jetty.webapp.JettyWebXmlConfiguration",//jettyWeb 
 });

DocumentServlet and UploadServlet

HttpServlet solution for uploading and downloading documents.

Example of upload servlet configuration:

 <servlet>
		<servlet-name>MaterialUpload</servlet-name>
		<servlet-class>cz.clever.cct.gwt.app.server.MyUploadServlet</servlet-class>
		<init-param>
	        <param-name>repository</param-name>
			<param-value>/tmp</param-value>
        </init-param>
        <init-param>
	        <param-name>maxMemSize</param-name>
			<param-value>2147483646</param-value>
        </init-param>
        <init-param>
	        <param-name>maxFileSize</param-name>
			<param-value>2147483646</param-value>
        </init-param>
	</servlet>

StringUtil

java.util.StringTokenizer is prohibited in the GWT client side. Here is my substitution:

 StringUtil.tokenizer("Jirka, Petr, Honza", ",", new ValueCallback() {
 
	@Override
	public void execute(String token) {
		// Your code
	}
 });

Way how to build a delimiter separated string from collection:

 ToString<MaterialOption> toStr = new ToString<MaterialOption>() {
 
	@Override
	public String get(MaterialOption obj) { //make a token from object
		return obj.toString();
		// or if you want: return obj == null? null:obj.getOptionString();
	}
 };
 // collection with filling of course
 Collection<MaterialOption> myCollection = new ArrayList<MaterialOption>();
 
 String result = StringUtil.toString(myCollection, ", ", toStr);

ParserCSV

 new ParserCSV(new ParserCSV.Delegate() {
 
			@Override
			public void token(String token, int position) {
				// working with parsed tokens
			}
 
			@Override
			public String getPath() { return "MyTable.csv"; }
 
			@Override
			public String getDelimeter() { return ";";}
 
			@Override
			public String getCharsetName() { return "UTF-16"; }
 });

BCrypt

String hashed = BCrypt.hashpw("password", BCrypt.gensalt());
boolean verified = BCrypt.checkpw("password", hashed);

String Externalizer (i18n)

Ant external task declaration example:

 <target name="externalizer">
		<taskdef name="externalizer" classname="cz.clever.gwt.ext.ant.Externalizer"/>
		<externalizer 
			        substitution="ClientConst.Util.get().%label()" 
			        labelMaxLength="20"
			        labelPrefix="lbl"
					fileConst="src/cz/clever/cct/gwt/app/client/ClientConst.java">
 
			        <fileset dir="src/cz/clever/cct/gwt/app/client">
			            <include name="*.java" />
			        	<exclude name="ClientConst.java"/>
			        </fileset>
			</externalizer>
	</target>

ClientConst.java (com.google.gwt.i18n.client.Constants) output example:

 @DefaultStringValue("Devices")
 String lblDEVICES();