1. Summary of the lecture We introduced the local variable dependency –This is a binary relationship (a relationship between two classes), similar to instantiation dependency –The difference is that the reference to the newly created object is stored in a local variable. –Example is on last two slides is of a local variable dependency between classes A (source) and B (target)

2. Variable declaration A variable declaration consists of two basic things: –the type of the variable –the name of the variable Java insists that all variables be declared before use – not all languages require this.

3. Why are types important Recall the discussion from early in the semester about how to interpret a string like “01001101” – the proper interpretation depends on the encoding scheme (e.g. two’s complement or IEEE754) The type of a variable tells the compiler, among other things, which encoding schemed to use to read/write data from/to the variable.

4. Instantiation Dependency in UML

5. class A – the source class package pkg; public class A { public A() { B b = new B(); }

6. class B – the target class package pkg; public class B { public B() { }