ClassOrInterfaceDeclaration.getTokenRange() gets all the tokens for a file even after removing nodes from the class

When I remove “ClassOrInterfaceDeclaration” nodes from a class in CompilationUnit (JavaParser) from a parsed file that contains more than one class, ClassOrInterfaceDeclaration.getTokenRange() gets all the tokens even the removed nodes tokens. For example, the code snippet at positions 1 and 2 will give the same result, although I already removed nodes from ClassOrInterfaceDeclaration n.

Does anyone know how to get the correct tokens list?

private void RemoveOtherClassesFromSameFile(ClassOrInterfaceDeclaration n) {
     n.getTokenRange() // 1
    List<ClassOrInterfaceDeclaration> internalClasses = unmodifiableList(
            n.getMembers().stream().filter(m -> m instanceof ClassOrInterfaceDeclaration)
                    .map(m -> (ClassOrInterfaceDeclaration) m).collect(toList()));
    for (ClassOrInterfaceDeclaration c : internalClasses)
        n.remove(c);
   n.getTokenRange() // 2
}

Answer

Ater Adjusting the file that contains the node, you must update the source root by using method saveAll, to override the AST to your file, like that

sourceRoot.saveAll(Paths.get(parsedFilePath));

Full Example:

import com.github.javaparser.ast.CompilationUnit;
import com.github.javaparser.ast.body.ClassOrInterfaceDeclaration;
import com.github.javaparser.ast.visitor.ModifierVisitor;
import com.github.javaparser.ast.visitor.Visitable;
import com.github.javaparser.utils.SourceRoot;

import java.io.IOException;
import java.nio.file.Path;
import java.nio.file.Paths;
import java.util.List;
import java.util.stream.Collectors;

public class Main {

    public  static  void main(String[] args) throws IOException {
        Path dirPath =  Paths.get("C:\JavaParserTest\src\main\resources\src\");
        SourceRoot sourceRoot = new SourceRoot(dirPath);
        sourceRoot.tryToParse();
        CompilationUnit cu = sourceRoot.parse("", dirPath.toString()+"\JavaFile.java");

        cu.accept(new ModifierVisitor<Void>() {
            @Override
            public Visitable visit(ClassOrInterfaceDeclaration n, Void arg) {
                RemoveOtherClassesFromSameFile(n, cu);
                return super.visit(n, arg);
            }
        }, null);

        sourceRoot.saveAll(Paths.get(dirPath.toString()+"\JavaFile.java"));
    }

    private static ClassOrInterfaceDeclaration RemoveOtherClassesFromSameFile(ClassOrInterfaceDeclaration n, CompilationUnit cu) {
        List<ClassOrInterfaceDeclaration> internalClasses = (
                n.getMembers().stream().filter(m -> m instanceof ClassOrInterfaceDeclaration)
                        .map(m -> (ClassOrInterfaceDeclaration) m).collect(Collectors.toList()));
        for (ClassOrInterfaceDeclaration c : internalClasses){
            n.remove(c);
        }
        return n;
    }

}