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Java Connectivity

The MinCor.NET Java Connectivity feature offers an easy and high performance solution to get 
interoperability between the .Net Compact Framework and Java. You can access EJB or Java 
objects implementing RMI remote interfaces. It is also possible to use and exchange Java 
serializable objects, catch exceptions thrown in Java or throw exceptions in .Net. If you 
have a running Java system all this is possible without any changes on the Java side. 
Many Java types are directly mapped to .Net types, e.g. java.util.Hashtable is mapped 
to System.Collections.Hashtable


The mapping is performed in two steps. During the first step Java is mapped to IDL 
and during the secound step IDL is mapped to .Net. IDL means Interface Definition Language. 
It is a specification published by the Object Management Group (OMG). In our main Demo 
we show the mapping of core IDL Types like: short, long, union, enum and so on. In the 
examples listed below we show how the mapping between .Net and Java works in a more general 
view with a focus on the Java language types.


In all the following examples we use Java as server and .Net as client. The Java server is
written as RMI server. The mapping is the same no matter which environment you are using: 
RMI on a Java server or EJBs on a J2EE server.

Content

	- Requirements
	- Remarks
	- Mapping for Java primitive types
	- Mapping for Java types

	First steps
	- Getting started - A simple "Hello" example

	Language mapping
	- Attributes - Java Attributes (set/get/is)
	- JavaNames - Java Names starting with $, _, ...
	- OverloadMethods - Method Signatures overloaded in Java
	- ObjectByValue - Java Serializables
	- Arrays - Multi Dimensional Array 
	- Collections - HashTable, ArrayList,...
	- InnerClasses - A Java Serializable with an Inner Class
	- Exceptions - Java User Exceptions

	Common patterns
	- Callback - Callbacks from Java to .Net

Requirements

	- Sun J2SE JDK 1.4.2 (www.java.sun.com)
	- Start the Sun name service (orbd). Use the batch 'MinCor\DemoJava\startNameService.bat'
	- Add 'MinCor\bin\MinCorCF.Dll' as reference to your .Net projects.
	- Add 'MinCor\bin\JavaBuildinTypesCF.Dll' (MinCor.Java-Feature) as reference to your .Net projects.
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Remarks

	Each example is located in a separate folder named 'MinCor\DemoJava\<NameOfExample>'.
	This folder comprises three subdirectories:

	'JavaServer': contains 2 batches:

	  - 'buildServer.bat'
	    Allows to create the 'server.jar', the IDL files and the .Net stub/skeleton code.
	  - 'startServer.bat'
	    Allows to start the server. Please, ensure that the Sun naming service is running
	    (s.f. section requirements).

	'DotNetClient': contains the .Net project for the client.
	  The client does not need any startup parameter, hence there is no startup batch.

	'IDL': contains the IDL file.
	  The IDL files are created by the 'buildServer.bat' batch.
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Mapping for Java primitive types

	Java          OMG IDL          .Net
	-----------------------------------------------
	void          void             void
	boolean       boolean          bool
	char          wchar            char
	byte          octet            byte
 	short         short            short
	int           long             int
	long          long long        long
	float         float            float
	double        double           double
	string        WStringValue     string
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Mapping for Java types


	Java                       	.Net
	-----------------------------------------------
	java.rmi.Remote            	Middsol.CORBA.Object
	
	java.math.BigInteger       	Middsol.java.math.BigIntegerHolder

	java.net.URI               	System.Uri
	java.net.URL               	System.Uri

	java.sql.Date              	System.DateTime
	java.sql.Time              	System.DateTime
	java.sql.TimeStamp         	System.DateTime

	java.util.ArrayList        	System.Collections.ArrayList
	java.util.Calender         	Middsol.java.util.CalenderHolder
	java.util.GregorianCalender	Middsol.java.util.GregorianCalenderHolder
	java.util.Date             	System.DateTime
	java.util.Hashtable        	System.Collections.Hashtable
	java.util.HashMap          	Middsol.java.util.HashMapHolder
	java.util.HashSet          	Middsol.java.util.HashSetHolder
	java.util.IdentityHashMap  	Middsol.java.util.IdentityHashMapHolder
	java.util.LinkedHashMap    	Middsol.java.util.LinkedHashMapHolder
	java.util.LinkedHashSet    	Middsol.java.util.LinkedHashSetHolder
	java.util.LinkedList       	Middsol.java.util.LinkedListHolder
	java.util.Locale           	System.Globalization.CultureInfo
	java.util.Properties       	Middsol.java.util.PropertiesHolder
	java.util.Random           	System.Random
	java.util.SimpleTimeZone   	Middsol.java.util.SimpleTimeZoneHolder
	java.util.Stack            	Middsol.java.util.StackHolder
	java.util.TreeMap          	Middsol.java.util.TreeMapHolder
	java.util.TreeSet          	Middsol.java.util.TreeSetHolder
	java.util.Vector           	Middsol.java.util.VectorHolder
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