Java: Risks, Benefits, and Potential Issues in Software Engineering, Slides of Introduction to Database Management Systems

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The Risks and Benefits of Software

Engineering with Java†

Identifying Relevant Issues

Strongest Potential Risks

 Unclear Standardization - A Political Hot Potato

 Microsoft and Apple - Partnership’s Impact on

Java

 Security Flaws and Java - A Constant Concern

 Performance - Will (Has?) HotShot VM Solve

Problem?

 Portability and Look-and-Feel: Has Platform

In(De)pendence been Achieved?

Identifying Relevant Issues

Most Significant Potential Benefits

 Programming Language Interactions - Cross Compilation, Byte-Code Generators, Translators  Client/Server and DOC - CORBA, ORBs, JNI, Legacy/COTS  Database/Persistence - Interactions with Relational/OO DBS

ALL THREE INVOLVE ENTERPRISE COMPUTING!!!

Assessing Risks and Benefits

 Java is Rapidly Evolving

 What are the Key Issues that Software Managers and Engineers Must Understand to Successfully Utilize Java?

 What are the Strongest Potential Risks for Switching to Java?

 What Capabilities of Java Provide the Strongest Case for the Technology?

 How Quickly Can Software Professionals Learn Java?

 What are the Long-Term Benefits of Java?

 How Can Java Interact with PLs, Legacy, and COTS?

Potential Risk 1: Standardization

 Unsettled Issue May Impact on Potential of Java

 Standardization Needed by Business/Government

 Sun asked International Standards Organization (ISO) to Declare Java as International Standard

 However, Sun wanted to Retain Sole Ownership

 US Delegation Against this Move - Supported by HP, Intel, TI, IEEE, etc.

 Other Nations (France, Great Britain) Back Sun

 Final Vote 20-2 in Favor of Sun: November 14, 1997

 Current Status: Java Standard May be Turned Over to Third Party Independent of Sun

Potential Risk 1: Standardization

 Without a Single Standard, Companies May Only Support Subsets of Java

 For Example, Sun Suing Microsoft Claiming that Internet Explorer Omits Vital Parts of Java

 Does Microsoft’s Version of Java Contain Features/Capabilities not in Sun’s Version?

 Multiple and Varied Subsets will Destroy Platform Independence

 Why Should One Switch to Java if Multiple Versions of ‘Same’ Software Maintained for Different Platforms?

 This is a Significant Con that Must be Monitored!

Potential Risk 2: Microsoft/Apple

 Con: Competing/Incompatible Java Versions will Significantly and Adversely Reduce its Attractiveness

 IBM, Sun, and Netscape Announced an Alliance to Cooperate on Java to Counter Microsoft’s Move

 Striving for Compatibility on All Platforms Including Win95 and NT

 Pro: Microsoft Move May Force Sun to Change their Standards Position

 Unknown: Strength and Productivity of Alliances

Potential Risk 3: Security Flaws

 Announcements in Mainstream Press of Flaws in Netscape or Explorer

 Flaw in Browser (or Software Application) May Result in a Java Applet Causing Damage During Execution

 August 1997 Bug in Internet Explorer

 Permitted an Applet to Open Network Connection to a Server Different from its Origin

 Violates Java Security Model

 Bug in Explorer Rather Than Java

Potential Risk 4: Performance

 Java has Poor Performance Reputation

 Execution Speed May Differ Substantially Across Platforms

 One Solution: Third-Party JVM Customization (Kaffe)

 Another Solution: Microsoft’s Win95 Java Performs Better than Sun’s Win95 Version of Java

 Yet Another Solution: Sun’s HotSpot JVM in 1.2 with Just-in-Time Compilation

 Con: Microsoft’s Own Version is Workable Assuming a Java Standard to Force Completeness!

Just-In-Time Compilation

Potential Risk 5 :

Portability and Look-and-Feel

 First Experience: CSE

 50+ Students given 41 “.class” Files and 4 “.java” Files with 3 weeks to Learn Java, html, and Modify/Extend Code  All But 1 or 2 Finished Project  CSE230 Now Java Based

 Platforms Utilized:  “.class/.java” Files Built on Solaris  Students Used Solaris, Win95/98/NT, Linux  Projects Graded on Solaris  Java Release Versions Caused Problems

 Successful from Learning/Course Perspective

 Students Indicated High Satisfaction with Project

Learning, Language, Environment 1 :

Similarity to C/C++/OO

 Non-OO Language Constructs of Java (Statements, Operators, Precedence, Declarations, etc.) Identical or Similar to C++

 OO Features Class, Inheritance, Exceptions - Strong Syntactic and Semantic Ties to C++

 Experience at UConn In Learning/Using Java

 30 Juniors/Seniors One Semester Significant Team Projects  50 Juniors Modify/Extend Existing Code Individual Project  50 Juniors with Java as CSE230 Language

 Background of SW Engineering, OO, and C++

 Pro: Similarity to C++ and Ease of Learning!

Learning, Language, Environment 2 :

Teaching Perspective

 Java has Emerged as an Excellent Teaching Language  Platform Independence - Instructor Can Avoid HW/OS Differences  ‘Free’ Compilers Across Platforms: Students Use/Download Familiar Platforms!  Easy to Learn if Know C++  Enforcement of Abstraction and Modularization with Class/Package Paradigms  Hiding Allows Controlled Sharing Between Classes with Alternate Visibility Choices  Pro: OO Java More Robust /Versatile than C++

Learning, Language, Environment 2 :

Teaching Perspective

 In a University Setting Java is Easily Established on Existing Hardware with Ease and Without Cost

 Students have Downloaded and Installed Java on Win95, NT, and Linux

 Availability of Shareware IDEs Provides Powerful Tools that Assist in Effectively Utilizing Java

 Java APIs Support Breadth of Domains and Applications Including Business, Engineering, GUIs, Embedded Systems, Databases, etc.

 Pro: Java in Classroom is a Strong Benefit!