Richard G Baldwin (512) 223-4758, NRG Room 4238, Baldwin@DickBaldwin.com, http://www.austincc.edu/baldwin

INEW2338 Advanced Java Programming

Spring 2014

Online Bulletin Board

Revised 11/05/13


Note:  The official web site for this course is located here.


In addition to Blackboard, this web page may be used for communicating information from Professor Baldwin to students enrolled in this course.

The online program named Blackboard will be used for communication with students in those cases where confidentiality is required, (such as the reporting of grades), posting announcements, sending email messages to individual students, and broadcasting email messages to all students enrolled in the course.

The Blackboard Assignment feature is the mechanism that you will use to submit your assignments.

The Blackboard "Send Email" feature is the mechanism that you will use to send Email messages to your instructor.

New messages are added to this bulletin board at the bottom of the list with the date that they were added.  Therefore, after reading all of the messages once, each time you check, you can go straight to the bottom to read the new messages.

Also, some of the messages have been repeated from previous semesters due simply to the fact that the information contained therein will be useful during this semester.


08/17/13 Warnings in JDK version 1.5 and later
As a result of changes (improvements?) made in JDK1.5, many existing programs will produce the following warning when recompiled using JDK 1.5:

Note: ....java uses unchecked or unsafe operations.
Note: Recompile with -Xlint:unchecked for details.

This topic is covered under Generics in ITSE 2317. This is a warning, and is not an error.  Dealing with this issue can significantly increase the complexity of program code. Therefore, insofar as this course is concerned, you can simply ignore the warning.

I have investigated the changes and have published material on how to avoid the warning on future programs.  However, it is extremely unlikely that I will modify and re-publish earlier programs that worked fine prior to the changes in the JDK.


08/17/13 Generics in J2SE 5.0
Several new features were incorporated into the release of JDK 1.5, also known as J2SE 5.0.  One of those new features is referred to as Generics.  On 04/05/05, I published my first tutorial lesson discussing the new features in J2SE 5.0, and explaining Generics in particular.  It would probably be worth your while to review this material.  You will find it in Lesson 2300 at http://www.dickbaldwin.com/tocadv.htm.  Among other things, this lesson explains the following compiler warnings that are frequently encountered when recompiling old programs:

Note: ....java uses unchecked or unsafe operations.
Note: Recompile with -Xlint:unchecked for details.


08/17/13 Do not send executable attachments
If you send an email message to me and expect me to read it, DO NOT attach any executable files, even if they are encapsulated in a zip file.  This includes files with the following extensions, just to name a few:

.exe
.com
.scr
.bat
.pif
.vb

If you do send such files, my virus blocker will simply reject the message and I will never see it.

The following file extensions should be OK:

.java
.class
.htm
.html
.css
.xml
.xsl
.doc
.zip (Provided the zip file doesn't contain any executable files.)

If you find it necessary to send a questionable file for any reason, you should also send another message without an attachment notifying me that you sent the questionable file as an attachment so that I can be on the lookout for it.


08/17/13 Exams are ready
Both exams are ready to be taken whenever you are ready to take them following the beginning of the semester.


08/17/13 Problems with the Java version and the path environment variable
A student of mine who had successfully compiled and executed Java programs on his system suddenly began to experience problems when trying to execute programs that had compiled successfully and had been run successfully in the past.

After a great deal of troubleshooting effort, this student determined that the recent installation of Oracle software for a database course that he was taking had caused an old version of the Java virtual machine to be installed on his system.  In addition, that installation had placed an element at the beginning of his path environment variable that caused the old version to be executed every time he attempted to execute a Java program.

If you experience problems when executing compiled Java programs from the command line, try entering the following command and confirming that you get a similar response (the first few digits of the version shown should be the same as the version that you installed):

C:\jnk\1>java -version
java version "1.7"
Java(TM) 2 Runtime Environment, Standard Edition (build 1.7...)
Java HotSpot(TM) Client VM (build 1.7..., mixed mode)

Similarly, if you experience problems when compiling Java programs, try entering the following command.  Your output should consist of about 25 lines of text, which should begin in a manner similar to the following.  Once again, the objective is to confirm the version.

C:\jnk\1>javac -version
javac 1.7
javac: no source files
Usage: javac lt;optionsgt; <source files>
where possible options include:
 ...

08/17/13 Don't use NetBeans, Eclipse, or other high-level IDEs
NetBeans, Eclipse, and other high-level IDEs are excellent productivity tools for programmers in the workplace who are working on large projects, who know exactly what they are doing, and who have a need to become more productive in their programming efforts.

However, to write the simple programs required for this course, you should need nothing more sophisticated than a text editor (preferably with Java syntax color coding) and the Sun Java Development Kit (JDK).  You shouldn't need a high-level IDE to serve as a crutch to help you write these simple programs.  The use of a high-level IDE to write the programs required for this course is a gross overkill, can lead to problems as illustrated by the following example, and is not recommended.

One of my students recently scored zero on an exam because he:

As a result, when I attempted to execute this student's programs in the prescribed manner, they all threw Exceptions or Errors and failed to execute.

Obviously, I can't keep you from using a high-level IDE to develop your programs on your system at home.  If you elect to do so, however, make certain that you understand exactly what you are doing, and also make certain that you test those programs in the prescribed manner.  Otherwise, you too may find that you won't get credit for the programs.


07/26/11 Your official Email address
All ACC students are provided an official Email address by ACC, and that address will be reflected in all official ACC student records.  I have been told that you can cause messages sent to that address to be forwarded to the Email address of your choice.

Also note that when it is necessary for me to send the same message to several students, I will send the message to your official ACC Email address using Blackboard. Therefore, you should make it point to either forward those messages, or to check your ACC email address on a daily basis.


07/15/12 DrJava
See Running DrJava at ACC-NRG at http://www.austincc.edu/baldwin/Spring14/Itse2321WebPage/ITSE2321RunningDrJavaAtACC.htm for information regarding the use of DrJava with Java 7.

07/15/12 Java and Ericson library version requirements
See the online syllabus for information regarding version requirements for Java and Ericson's media library.

I have performed spot checks to confirm that the study guides, the assignments, and the exams are all compatible with those version requirements.  With the exception of some compiler warnings caused by features that were introduced in JDK 1.5, I haven't found any problems.  However, it is possible that I may have missed something.

When you compile source code used in this course, you may get compiler warnings as a result of features that were introduced in JDK 1.5.  This is particularly true if the source code uses the Java Collections Framework.

Please notify me if you discover any situation where the features that were introduced in JDK 1.5 or later versions cause problems with the study guides, the assignments, or the exams so that I can correct the situation for future semesters.


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