这是理解重要性的一个例子运营商优先权。

This is an example of the importance of understanding operator precedence.

您需要括号，否则会被解释如下：

You need the parentheses otherwise it is interpreted as follows:

String test = ("test" + testInteger) == null ? "(null)" : testInteger.toString();

请参阅这里列出了运营商及其优先顺序。另请注意该页面顶部的警告：

See here for a list of operators and their precedence. Also note the warning at the top of that page:

注意：甚至可能出现混淆时使用明确的括号。

Note: Use explicit parentheses when there is even the possibility of confusion.