Signature File Merge Rules

The -Filesargument of the SignatureTest command accepts values to specify one or more signature files that are combined to represent an API configuration that is used as input for testing. This resulting API-set can also be combined into a single signature file for testing purposes.

By default the API combination is assumed to be constructed according to the JSR 68 rules. This can be overridden during a SigTest tool test run by specifying the -NoMergeoption to run the signature test. The -NoMergeoption forces SigTest tool to use the first class description it encounters if more than one class with the same name is found in the set of signature files specified by the -Filesargument. In this case it uses the class from the left-most signature file that is specified with -Files.

JSR 68-Based Merge

The Java ME platform architecture specified by JSR 682 allows for the inclusion of several Java platform APIs in one conforming Java platform runtime environment. The condition for combining these APIs is that any application written for the resulting runtime environment must execute successfully on the combination.

If such a combination exists, it is defined on the basis of the combined sets of APIs with semantics, and the semantics must be compatible with those of all the included components.

The only means of verifying the semantics of the combination is to run the applicable test suite for each API. However, it is possible to automate the creation of a combined set of API signatures, and it is also possible to detect when a combined set cannot be built.

The Merge command functionality combines (merges) several input signature files into one resulting signature file, as follows: If A, B, and C are signature files, then A

+B yields signature file C, and each of the three signature files represent the corresponding classes of their respective APIs. The Merge process constructs the resulting API C out of the two input APIs A and B.

Merge Command Operative Principles

The Merge command operates according to the following principles, where A and B are input APIs that are combined into the resulting API C:

2.http://jcp.org/en/jsr/detail?id=68

Chapter 2 Using the Signature Test Tool

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Sun Microsystems 2 manual Signature File Merge Rules, JSR 68-Based Merge, Merge Command Operative Principles
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2 specifications

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