Advantages(Pros):
- Easier to learn than c++
- Easier to read code than c++
- More rapid and potentially less error-prone development (due to less memory management) than c++.
- Most cross-platform since it was designed for it and Sun makes JREs and JDKs for most platforms
- All things are passed by reference except for value types, by default
- Garbage collector cleaning up objects once they're no longer used, so you don't have to manually track everything yourself
- Apparently java 6 runs (some?) stuff slightly faster than c++ (test code ported from c++ ran faster despite having to do seemingly wasteful things!)
- Program is compiled and optimized for the platform it's on, if necessary?
- Easy to make multiple threads, and you can declare functions synchronized so only one thread can be in them at a time (IIRC)
- You can use wait() and notifyAll() and notify() to suspend threads to wait for signals and wake them up again.
- Various free IDEs available on all platforms, such as Eclipse
- If the program crashes, it should either tell the user where in the code and why, showing a stack trace including line numbers (if debug symbols are enabled or something like that), or it can be dumped to an error log file.
- Programs can be packaged into jar files with various data files in different jar files and accessed by users using Java WebStart, which will auto-update the program and any other needed jar files to the latest version, only downloading what jar files have changed.
- Easier/more cross-platform networking than c++.
- Files are read and written as big-endian on all platforms (which is network byte order) ensuring that communications between java programs and file loading never require byte-order swapping (unless talking to a non-java program or using a file written by one).
Disadvantages(cons):
- Uses more memory than c++ or c#
- JNI is terrifying, but if we're being cross-platform we probably won't use it, (except that the 3d engine will?)
- Garbage collector using CPU cycles and memory - (but barely any, at least CPU time)
- No unsigned integers
- No pointers, no ref or out parameters (which replace pointers in c#). To return multiple things from a java function you tend to have to return an object[] holding each thing, or make a class which holds each thing and return an object of that class.
- Some things were renamed - const is final in java, for example
- Java does not allow indexers or operators on objects, e.g. if you use resizable lists etc, you have to do list.get(index) instead of list[index], and you can't do someVector + someOtherVector.
- Java does not let you decide whether a type should be a value or a reference type (determining if it should be pass by value or pass by reference), unlike c#.
- Jar files used by java webstart have to be signed with a certificate. Code signing certificates cost hundreds of dollars per year, or you can make a self-signed one and use that, which will make Java Webstart pop up a "This certificante can't be verified" dialog when the user tries to run the program. (Alternately, don't use Java Webstart and just distribute jar files directly - which requires users to check for updates themselves.)
- Requires a JRE to be installed to run the program, which is a several hour download on dialup.
- Have to use java 5 for generics, 1.4 doesn't have them. Java 6 is newest and a couple years old, but - Apple releases their own java versions for Mac users, and still hasn't released a "stable" java 6 version for its users.
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