Java Reference
In-Depth Information
Figure 2-14.
Step 1: The programmer enters the source code
Step 2: The source code is translated into bytecode by the compiler
Step 3: The bytecode is translated into machine language by the JVM and sent to the CPU to be executed
In Chapter 1, you performed step 1 when you typed in the source code using the RAD editor. When you saved
the source code, RAD performed step 2 and when you clicked the Run button RAD performed step 3.
Please notice two important items in Figure
2-14
, the
.java
file and
.class
file. Source code is stored in a file
with an extension of “java” (i.e., EmployeeApp.java) and bytecode is stored in a file with an extension of “class”
(i.e., EmployeeApp.class). The RAD Java perspective hides the class files. However, RAD did show the Java file
names both in the Content pane tabs and the Navigation tree (see Figure
2-13
).
Let's take a more detailed look at the JRE using RAD and the online documentation. In addition, we'll prove that
RAD does steps 2 and 3 as stated above.
Tutorial: Exploring the JRE with RAD
Now let's start exploring:
1.
If necessary, start RAD.
RAD “remembers” what was worked on last. As long as you are using the same PC and no one else has used RAD
since you did, RAD will display MyFirstProject in the Java perspective and any source code that was left open in the
content pane.
