如何使用ASTRewrite来替换一个具有PrimitiveType的特定SimpleType？ [英] How to use ASTRewrite to replace a particular SimpleType with a PrimitiveType?

问题描述

我需要在编译基于Java的语言（Processing）之前对一些代码进行预处理。在这种语言中，所有颜色的实例都需要用int替换。例如，以下是代码片段：

I need to preprocess some code before compiling for a java based language - Processing. In this language, all instances of type color, need to be replaced with int. For ex, here's a code snippet:

color red = 0xffaabbcc;
color[][] primary = new color[10][10];

预处理后，上述代码应如下所示：

After preprocessing, the above code should look like:

int red = 0xffaabbcc;
int[][] primary = new int[10][10];

我在非eclipse环境中工作。我正在使用Eclipse JDT ASTParser来执行此操作。我实现了我的ASTVisitor访问所有SimpleType节点。以下是ASTVisitor实现的代码片段：

I'm working in a non eclipse environment. I'm using Eclipse JDT ASTParser to do this. I've implemented my ASTVisitor which visits all SimpleType nodes. Here's the code snippet from the ASTVisitor implementation:

public boolean visit(SimpleType node) {
    if (node.toString().equals("color")) {
        System.out.println("ST color type detected: "
                + node.getStartPosition());
        // 1
        rewrite.replace(node,
                rewrite.getAST().newPrimitiveType(PrimitiveType.INT), null);
        // 2
        node.setStructuralProperty(SimpleType.NAME_PROPERTY, rewrite
                .getAST().newSimpleName("int")); // 2
    }
    return true;
}

这里重写是ASTRewrite的一个实例。
第1行没有效果（第2行注释掉）。并且第2行导致IllegalArgumentException被抛出，因为newSimpleName（）将不接受任何java关键字，如int。

Here rewrite is an instance of ASTRewrite. Line 1 has no effect(with line 2 commented out). And line 2 causes IllegalArgumentException to be thrown because newSimpleName() will not accept any java keywords like int.

查找并替换所有颜色与正则表达式的实例似乎不像正确的方式，因为它可能会导致不必要的变化。但是我可能错了。

Finding and replacing all instances of color with regex doesn't seem like the right way to me since it could cause unnecessary changes. But I may be wrong.

我该如何实现？或者有什么替代的解决方案或方法我可以采取？

How can I achieve this? Or are there any alternate solutions or approaches I can take?

谢谢

更新编辑：
这是执行ASTRewrite的代码段：

Update Here's the snippet which performs ASTRewrite:

    CompilationUnit cu = (CompilationUnit) parser.createAST(null);
    cu.recordModifications();
    rewrite = ASTRewrite.create(cu.getAST());
    cu.accept(new XQASTVisitor());

    TextEdit edits = cu.rewrite(doc, null);
    try {
        edits.apply(doc);
    } catch (MalformedTreeException e) {
        e.printStackTrace();
    } catch (BadLocationException e) {
        e.printStackTrace();
    }

XQAstVisitor是包含上述访问方法的访问者类。还有其他替代，我执行正确执行。只有这一个会导致问题。

XQAstVisitor is the visitor class which contains the above visit method. There are other substitution that I'm performing that execute correctly. Only this one causes problems.

推荐答案

我发现你的错误！
此语句：

I found your errors! This statement：

TextEdit edits = cu.rewrite(doc, null);

不正确。
应该由以下语句替换：

is not right. And should be replaced by the following statement:

TextEdit edits = rewrite.rewriteAST(doc, null);

最后，再次将修改的文档解析为CompilationUnit，将应用更改。
此外，语句：

In the end, parse the modified doc into CompilationUnit again, the changes will be applied. What's more, the statement:

node.setStructuralProperty(SimpleType.NAME_PROPERTY, rewrite.getAST().newSimpleName("int"));

不需要。

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