As there are more tools and concepts added in the JDK 5.0, the compiler is also enhanced to process these changes. The support for all the enumeration and for each loop is also added. The following compiler options are also added in the compiler in JDK1.5.

• -source 1.5 - Enable 1.5 specific language features to be used in source files. ( -target 1.5 is implied.)


• -target 1.5 - Allow javac to use 1.5 specific features in the libraries and virtual machine.


• -Xlint - Enable javac to produce warning messages about legal, but suspect and often problematic, program constructs. An example would be declaring a class that implements Serializable but does not define a serialVersionUID .


• -d32 - Indicate a 32-bit Solaris or Linux platform.


• -d64 - Indicate a 64-bit Solaris or Linux platform.


• -target cldc1.0 - Generate class files suitable for use on VMs in Connected Limited Device Configuration (CLDC) version 1.0 and later. The compiler generates stack maps making the use of the preverifier unnecessary.

Java Platform Debugger Architecture (JPDA)

JPDA has following new features:-

• A read-only subset of JDI has been defined. This subset can be used on a debuggee in which no debug code can be executed. The subset allows creation of JDI connectors for use in debugging such debuggees.


• A service provider interface for connectors and transports allows end users, to create their own JDI connectors and transports and plug them into the JPDA reference implementation.


• JDI supports the new language features (generics, enums, and varargs).


• The layers Java Virtual Machine Debugger Interface (JVMDI) and Java Virtual Machine Profiling Interface (JVMPI), has been deprecated and will be removed in the next major J2SE release. A new layer Java Virtual Machine Tool Interface (JVMTI) is introduced which is a more general interface that allows profiling to be done as well as debugging.


• The JPDA reference implementation includes new JDI connectors that allow core files and hung processes to be debugged.