How can I display line numbers in Java?

In Java, you can display line numbers by using line numbering. This can be achieved in two ways.

1. Utilizing Exception Stack Trace Information: In Java, you can access the current line number by retrieving the exception stack trace information. For example, you can use a try-catch block to catch an exception, and then print the stack trace information, which includes line number information. Here is an example code snippet:

try {
    throw new Exception();
} catch (Exception e) {
    e.printStackTrace();
}

After executing the above code, it will print out the stack trace of the exception, which includes line numbers.

1. Using the StackTraceElement class: Java offers the StackTraceElement class, which allows you to retrieve the call stack information of the current method. You can display the line number by obtaining the stack trace of the current thread and then getting the current line number. Example code is as follows:

StackTraceElement[] stackTrace = Thread.currentThread().getStackTrace();
int lineNumber = stackTrace[1].getLineNumber();
System.out.println("当前所在行数：" + lineNumber);

After running the above code, the current line number will be printed.

It’s important to note that both methods mentioned above rely on obtaining line number information from the exception stack trace, which may result in some performance overhead.