从 JAVA 源 AST 中删除所有方法调用答案

【问题标题】：Remove All Methodinvocation from JAVA Source AST从 JAVA 源 AST 中删除所有方法调用
【发布时间】：2014-12-18 17:41:58
【问题描述】：

您好，我找到了所有 Methodinvocation 和 ASTVisitor 并将删除所有 ASTRewrite 但是当使用“for 循环”删除方法时，只删除第一个调用事件的方法调用。我猜问题原因不刷新 AST 、 CompiliationUnit 、 ICompilationUnit 或 ASTRewrite 但我不知道何时以及如何刷新它以在第一个事件中全部删除。

static void createAST(ICompilationUnit unit) throws JavaModelException {
    // now create the AST for the ICompilationUnits
    CompilationUnit parse = parse(unit);
    MethodVisitor visitor = new MethodVisitor();
    parse.accept(visitor);
    for (MethodInvocation metInv : visitor.getMethods1()) {
        try {
            //if declarated by user. 
            if (metInv.resolveMethodBinding().getDeclaringClass().isFromSource()) {
                methodInvocRemove(unit, metInv);
            }
        
        } catch (Exception e) {
            System.out.println("EXCEPOTION:" + e.getMessage());
        }
    }
}

此方法用于删除所有 MethodInvocations。

private static void methodInvocRemove(ICompilationUnit unit, MethodInvocation met) {
    try {
        IProject project = unit.getJavaProject().getProject();
        CompilationUnit astRoot = parse(unit);
        // create a ASTRewrite
        AST ast = astRoot.getAST();
        ASTRewrite rewriter = ASTRewrite.create(met.getParent().getParent().getAST());
        rewriter.remove(met.getName().getParent(), null);
        TextEdit edits;
        edits = rewriter.rewriteAST();
        Document document = new Document(unit.getSource());
        edits.apply(document);
        // this is the code for adding statements
        unit.getBuffer().setContents(document.get());
        unit.getBuffer().close();
    } catch (MalformedTreeException e) {
        System.out.println("EXP!!!" + e.getMessage());
    } catch (BadLocationException e) {
        System.out.println("EXP!!!" + e.getMessage());
    } catch (JavaModelException e) {
        System.out.println("EXP!!!" + e.getMessage());
    } catch (IllegalArgumentException e) {
        System.out.println("EXP!!!" + e.getMessage());
    }
}

此方法用于使用 ASTVisitor 进行查找方法调用。在eclipse JDT上的每个事件之后调用这个方法。

public static void findMethod(IProject project) {
    try {
        if (project.isNatureEnabled("org.eclipse.jdt.core.javanature")) {
            IPackageFragment[] packages = JavaCore.create(project).getPackageFragments();
            for (IPackageFragment myPack : packages) {
                if (myPack.getKind() == IPackageFragmentRoot.K_SOURCE) {
                    for (ICompilationUnit unit : myPack.getCompilationUnits()) {
                        CompilationUnit parse = parse(unit);
                    }
                }
            }
        }
    } catch (CoreException e) {
        System.out.println("EXP!!!"+e.getMessage());
    }
}

用于解析和修改的Java文件示例代码。

public class MethodInvoc {

private void invoc1()
{
    MethodDeclar object1 = new MethodDeclar();
    System.out.println(object1.getStr());
}

private void invoc2() {
    MethodDeclar object2 = new MethodDeclar();
    System.out.println(object2.getStr());
}

private void invoc4()
{
    MethodDeclar object3 = new MethodDeclar();
    System.out.println(object3.getStr());
}
}

调用事件并运行methodInvocRemove后，上面的代码改为：

 public class MethodInvoc {

private void invoc1()
{
    MethodDeclar object1 = new MethodDeclar();
    System.out.println();
}

private void invoc2() {
    MethodDeclar object2 = new MethodDeclar();
    System.out.println(object2.getStr());//not change this :( 
}

private void invoc4()
{
    MethodDeclar object3 = new MethodDeclar();
    System.out.println(object3.getStr());//not change this :( 
}
}

【问题讨论】：

标签： java eclipse abstract-syntax-tree eclipse-jdt

【解决方案1】：

您需要为每个CompilationUnit 缓存您的ASTRewrite，删除所有带有ASTRewrite.remove(...) 的MethodInvocation 节点，然后只应用一次所有编辑。

所以在伪代码中：

ASTRewrite rewriter = ASTRewrite.create(astRoot.getAST());
for (MethodInvocation metInv : getAllMethodInvocationsToRemove()) {
    rewriter.remove(metInv, null);
}
unit.applyTextEdit(rewriter.rewriteAST(), new NullProgressMonitor());

要在rewriter 中应用编辑，我对这段代码（其中unit 是ICompilationUnit 的一个实例）有很好的经验，而不是使用Document：

unit.applyTextEdit(rewriter.rewriteAST(), new NullProgressMonitor());

您可能还想查看这篇文章，并使用ICompilationUnit.becomeWorkingCopy 和ICompilationUnit.commitWorkingCopy 来包装您的更改：Eclipse AST not changing files which are not opened in eclipse

【讨论】：