Introduction - Java Software Solutions: Foundations of Program Design - page 40

Java source
code

Java
bytecode

Java compiler

Java
interpreter

Bytecode
compiler

Machine
code

FIGURE 1.21

The Java translation and execution process

distinct advantage of making Java architecture neutral, and therefore easily por-
table from one machine type to another. The only restriction is that there must
be a Java interpreter or a bytecode compiler for each processor type on which the
Java bytecode is to be executed.
Since the compilation process translates the high-level Java source code into
a low-level representation, the interpretation process is more efficient than inter-
preting high-level code directly. Executing a program by interpreting its bytecode
is still slower than executing machine code directly, but it is fast enough for
most applications. Note that for efficiency, Java bytecode could be compiled into
machine code.

Development Environments
A software development environment is the set of tools used to create, test, and
modify a program. Some development environments are available for free while
others, which may have advanced features, must be purchased. Some environ-
ments are referred to as integrated development environments (IDEs) because
they integrate various tools into one software program and provide a convenient
graphical user interface.
Any development environment will contain certain key tools, such as a Java
compiler and interpreter. Some will include a debugger, which helps you find