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Using PPA GUI Tools

You can execute PPA on any java source files or code snippets in your Eclipse workspace: PPA will traverse the abstract syntax tree of the java source file and print the type of each node in the console.

These GUI tools enable you to try PPA without writing a single line of code. You can also use this tool to submit a bug report by providing the actual output of PPA and telling us the output you expect.

Analyzing a Java source file in a Java project

Suppose that you have a Java file, MyApplication.java, in a Java project:

Java Source file from an incomplete Java program.

This source file references classes for which you do not have the declaration (e.g., Animal). In the Package Explorer view, right-click on the MyApplication.java file and choose: PPA -> Run PPA (ICompilationUnit). A console will appear with a walk of the Abstract Syntax Tree, showing each name element with its corresponding type information:

Console displaying an AST walk of the partial program.

For example, you can see that the node new Animal() is associated with the method binding void p1:Animal:<init>(), which is the binding of the constructor of type p1.Animal. The standard Eclipse compiler would usually not produce this binding, because the declaration of Animal is missing. If you look further down in the console, you will see that the binding associated with the printInfo method is: UNKNOWNP.UNKNOWN p1.Animal:printInfo(int,java.lang.String). In this case, PPA has inferred the container of the method, the parameters' types and the container's type.

Analyzing a Java source file

It is also possible to analyze a complete Java source file that is not in a Java project:

Java source file not in a Java project

Again, this source file references classes for which you do not have the declaration such as Animal and also java.lang.String. Notice that because this file is not part of a source folder in a Java Project, the editor does not show any compiler error. In the Package Explorer view, right-click on the MyApplication.java file and choose: PPA -> Run PPA (File). A console will appear with a walk of the Abstract Syntax Tree, showing each name element with its corresponding type information.

Analyzing a code snippet

It is sometimes desirable to analyze snippets of code. Currently, only lines of code that represent a method body (i.e., lines without a method header) or a class body (lines without a class header) are supported. Suppose that you have a snippet of code in a text file:

Snippet of Java code

This source file references classes for which you do not have the declaration such as Animal and also java.lang.String . In the Package Explorer view, right-click on the Snippet.txt file and choose: PPA -> Run PPA (Method Body Snippet). A console will appear with a walk of the Abstract Syntax Tree, showing each name element with its corresponding type information.

Analyzing a single element in a Java source file

Finally, if you want to know the binding of a particular name element (e.g., a method call, a variable, etc.), you can select a particular name in a Java editor, right-click on it and then select PPA -> Run PPA (Name):

Getting information for a Java name element.

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