How to Obtain Return Values in Static Analysis of Java

Thank you for your help.

Currently, we are conducting static analysis of java in java and would like to get the return value of the method.
I was able to get the method name using imethod, but I don't know how to get the return value.

For example, if the method says the following, I would like to get the variable name hoge instead of the return value (0 in this case).

public int hoge(){
  inthoge = 0;
  return hoge
}

That's all.
Thank you for your cooperation.

java

2022-09-30 11:50

1 Answers

Since you are using IMethod, you assume that you are trying to retrieve the expression specified in the return statement from the class file, but I don't think you can get the necessary information.
The class file does not appear to contain the source code information for the return statement.
I tried using the javap command or hexadecimal dump, but I couldn't find any information.

You can use node.getExpression() to get the information you need within the visit method, where ReturnStatement node is the provisional argument by creating a class that inherits ASTVisitor.

Statically parsed code

public class Myclass{
    public into hoge() {
        intret;
        return ret*2;
    }
}

Retrieved Results
ret*2

code

import org.eclipse.core.runtime.NullProgressMonitor;
import org.eclipse.jdt.core.dom.ASTParser;
import org.eclipse.jdt.core.dom.ASTVisitor;
import org.eclipse.jdt.core.dom.CompilationUnit;
import org.eclipse.jdt.core.dom.ReturnStatement;

import static org.eclipse.jdt.core.dom.AST.JLS8;

public class Main {
    public static void main(String[]args) {
        String source = "public class Myclass {" +
                "   public int hoge() {\r\n" +
                "       intret=0;\r\n"+
                "       return ret*2;\r\n"+
                "   }\r\n"+
                US>"}\r\n" +
                "";
        System.out.println(source);
        ASTParser parser = ASTParser.newParser (JLS8);
        parser.setSource(source.toCharArray());
        CompilationUnit=(CompilationUnit) parser.createAST(new NullProgressMonitor());

        MyVisitor visitor = new MyVisitor();
        unit.accept(visitor);
        System.out.print("END");
    }
}

class MyVisitor extensions ASTVisitor {
    @ Override
    public boolean visit (ReturnStatement node) {
        System.out.println("node=["+node.toString()+"]");
        System.out.println("node.getExpression()=["+node.getExpression().toString()+"]");
        return super.visit(node);
    }
}

Run Results

node=[return ret*2;
]
node.getExpression() = [ret*2]

2022-09-30 11:50

If you have any answers or tips

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