java - 如何获取变量的构造函数？

我正在尝试使用ASTVisitor获取变量的构造函数。

public boolean visit(VariableDeclarationFragment node)
{
    IVariableBinding variableBinding = node.resolveBinding();

    // I can't seem to get the constructor here
}

样品

Base b = new Derived(); // How do I get packageNAME.Derived?
int x = 5; // How do I get 5?

最佳答案

您需要更深入地研究语法树以找到答案。在这种情况下，ASTView是一个很大的帮助。这是我与开普勒一起使用的更新站点：http://www.eclipse.org/jdt/ui/update-site

您的样本可以这样回答（简化）：

/*
 * Base b = new Derived(); // How do I get packageNAME.Derived?
 */
private String getClassNameFromConstructor(VariableDeclarationFragment fragment) {
    Expression initializer = fragment.getInitializer();
    if (initializer instanceof ClassInstanceCreation) {
        ClassInstanceCreation instanceCreation = (ClassInstanceCreation)initializer;
        if (instanceCreation.getType() instanceof SimpleType) {
            SimpleType simpleType = (SimpleType)instanceCreation.getType();
            return simpleType.getName().getFullyQualifiedName();
        }
    }
    return null;
}

/*
 * int x = 5; // How do I get 5?
 */
private String getInitialisationNumber(VariableDeclarationFragment fragment) {
    Expression initializer = fragment.getInitializer();
    if (initializer instanceof NumberLiteral) {
        NumberLiteral numberLiteral = (NumberLiteral)initializer;
        return numberLiteral.getToken();
    }
    return null;
}