Eclipse抽象语法树程序化访问

Question

您是否可以提供一个以编程方式访问Eclipse Abstract Syntax Tree的示例代码？

例如获取AST：

---

Class1.java

package parseable;

public class Class1 {

/**
 * @param args
 */
public static void main(String[] args) {
    System.out.println("Hello world!");
}

}

Answer 1

这不是一个完全的答案，可能会给你一个开始的地方：

正如question中所说，

此eclipse corner article中提供了完整示例，eclipse help中还提供了更多详细信息。在this presentation的幻灯片59中，您可以看到如何对源代码应用更改。

Answer 2

// get an ICompilationUnit by some means
// you might drill down from an IJavaProject, for instance 
ICompilationUnit iunit = ...

// create a new parser for the latest Java Language Spec
ASTParser parser = ASTParser.newParser(AST.JLS3);

// tell the parser you are going to pass it some code where the type level is a source file
// you might also just want to parse a block, or a method ("class body declaration"), etc
parser.setKind(ASTParser.K_COMPILATION_UNIT);

// set the source to be parsed to the ICompilationUnit
// we could also use a character array
parser.setSource(iunit);

// parse it.
// the output will be a CompilationUnit (also an ASTNode)
// the null is because we're not using a progress monitor
CompilationUnit unit = (CompilationUnit) parser.createAST(null);

不要被ICompilationUnit与CompilationUnit区分混淆，这似乎只是他们自己命名的命名的结果。 CompilationUnit是一种ASTNode。此上下文中的ICompilationUnit类似于文件句柄。有关区别的更多信息，请参阅此处：http://wiki.eclipse.org/FAQ_How_do_I_manipulate_Java_code%3F