12.10.3. Implementation of Registry Access Functions as Native Methods

We need to implement three actions:

• Get the value of a name

• Set the value of a name

• Iterate through the names of a key

Fortunately, you have seen essentially all the tools that are required, such as the conversion between Java strings and arrays and those of C. You also saw how to raise a Java exception in case something goes wrong.

Two issues make these native methods more complex than the preceding examples. The getValue and setValue methods deal with the type Object, which can be one of String, Integer, or byte[]. The enumeration object stores the state between successive calls to hasMoreElements and nextElement.

Let us first look at the getValue method. The method ...

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