Objects and classes - Objects First with Java: A Practical Introduction Using BlueJ - page 10

Figure 1.7
A class and its
objects with fields
and values

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Figure 1.8
Two images created
from a set of shape
objects

1.9 Java code

When we program in Java, we essentially write down instructions to invoke methods on
objects, just as we have done with our figure objects above. However, we do not do this
interactively by choosing methods from a menu with the mouse, but instead write the com-
mands down in textual form. We can see what those commands look like in text form by
using the BlueJ Terminal.