Question

我想将当前代码转换为Java7 diamond operator。我有以下正则表达式来查找和替换。

查找

new (\w+)<.+>

替换：

new $1<>

问题在于也被替换为匿名类。由于这个我得到编译错误。那么如何编写避免内部类的正则表达式呢？

Answer 1

试试这个：(?s)new (\w+)<.+>(\(.*?\);)

String test = "List<String> t = new ArrayList<String>();";
System.out.println(test.replaceAll("(?s)new (\\w+)<.+>(\\(.*?\\);)", "new $1<>$2"));

String test2 = "List<String> t = new ArrayList<String>(getList());";
System.out.println(test2.replaceAll("(?s)new (\\w+)<.+>(\\(.*?\\);)", "new $1<>$2"));

String test3 = "List<String> t = new ArrayList<String>(\n\tgetList(\n\t\tanotherMethod()\n\t)\n);";
System.out.println(test3.replaceAll("(?s)new (\\w+)<.+>(\\(.*?\\);)", "new $1<>$2"));

String test4 = "List<String> t = new List<String>(){ /* implementation */ };";
System.out.println(test4.replaceAll("(?s)new (\\w+)<.+>(\\(.*?\\);)", "new $1<>$2"));

String test5 = "List<String> t = new List<String>()\n{\n\t/* implementation */\n};";
System.out.println(test5.replaceAll("(?s)new (\\w+)<.+>(\\(.*?\\);)", "new $1<>$2"));

打印：

List<String> t = new ArrayList<>();
List<String> t = new ArrayList<>(getList());
List<String> t = new ArrayList<>(
    getList(
        anotherMethod()
    )
);
List<String> t = new List<String>(){ /* implementation */ };
List<String> t = new List<String>()
{
    /* implementation */
};

java7钻石运算符转换编译错误

1 个答案: