java code 128 Comparing Java and .NET Technologies in Visual Basic .NET

Encoder Code-128 in Visual Basic .NET Comparing Java and .NET Technologies

1, "Introduction to Microsoft .NET," presented a high-level introduction to Microsoft .NET, comparing it both conceptually and technologically with Java. This chapter extends that discussion but focuses more deeply on the technology provided by the two platforms.

Although this book focuses predominantly on the .NET functionality that is directly comparable to that of Java 2 Standard Edition (J2SE) version 1.4, this chapter also covers functionality provided by Java 2 Enterprise Edition (J2EE) version 1.3.1. Many Java programmers work with both J2SE and J2EE, and although .NET has a ways to go before it competes with J2EE, it's useful to demonstrate the current features that are comparable and the alternative technologies to use where there are gaps. We don't discuss APIs that aren't part of J2SE and J2EE: they provide compelling and interesting functionality, but it's simply not possible to cover every Java API, and it's often difficult to make substantive comparisons. This is true even for the new Java XML APIs. Although they will help to address the imbalance between the XML capabilities of Java and those of .NET, at the time of this writing they are still in early access release. Also, we haven't included a comparison of Java 2 Micro Edition (J2ME) and the Microsoft .NET Compact Framework. Each is important to the Sun and Microsoft consumer device strategies, but they are topics deserving of their own books.

When viewed holistically, the Java and .NET platforms are comparable: both provide solutions to most contemporary business computing issues. However, when the platforms are broken down into functional components, mapping between the constituent parts is often very loose. The .NET class library doesn't yet encompass all the functionality found in the J2EE class libraries and often needs to utilize other Microsoft technologies to provide a complete solution; we expect that these technologies will become more tightly integrated as the .NET platform matures. Despite these inconsistencies, we proceed with a liberal attitude, presenting technology alternatives that are accessible from the .NET platform even though they are not explicitly part of it.

Namespaces are the mechanism used to provide categorization and structure in the .NET class libraries. We discuss namespaces in 4, "Language Syntax and Features," but for now it's enough to understand that namespaces are analogous to Java packages.

Table 2-1 shows .NET technology alternatives to the major components of the J2SE platform as broken down within the J2SE platform documentation.

The .NET class libraries contain functionality that is broadly comparable to the Java Lang and Util APIs. However, the diverse nature of the functionality in these two APIs makes it impossible to provide a useful highlevel functionality mapping. For more information, see Appendix F, "Java to .NET API Reference", which provides a class-level mapping between the Java and .NET class libraries. New I/O The New I/O API is a collection of features and performance improvements new to J2SE version 1.4. Many of these features provide functionality that is already available in .NET, including regular expressions, asynchronous I/O, and character encoding. In .NET, asynchronous I/O capabilities are incorporated directly into the standard networking and Stream classes. Both 10, "Streams, Files, and I/O," and 14, "Networking," provide details of the asynchronous I/O capabilities provided by the .NET classes. Regular expressions and character encoding are both covered in 7, "Strings and Regular Expressions." Networking The System.Net namespace of the .NET class library contains functionality comparable to that of the Java networking classes. Consult 14 for complete details. Preferences Along with the Microsoft Windows registry, .NET provides a mechanism called isolated storage. Together, these features provide the technology that is most comparable to the Java Preferences API. We discuss isolated storage in 10 and discuss the Windows registry in Appendix A, "Platform Integration." Collections The System.Collections namespace of the .NET class library includes Framework functionality comparable to the Java Collections Framework. 9, "Collections," provides a detailed discussion of .NET collections. Java Native JNI provides access to platform-specific functionality from the platformInterface (JNI) neutral environment provided by Java. As a Windows-based environment, .NET doesn't face these issues. However, .NET does provide the Platform Invocation Service (PInvoke), which allows calls to functions contained in unmanaged libraries. .NET also includes extensive capabilities for interoperability with COM components. Security The .NET Framework provides a comprehensive security system, which can be used to grant or deny platform features to applications. 17, "Security and Cryptography," provides a discussion of the .NET security system.