Showing a Spring transaction in log

Question

I configured spring with transactional support. Is there any way to log transactions just to ensure I set up everything correctly? Showing in the log is a good way to see wh

Answer 1

Here is some code I use in my Logback Layout implementation derived from ch.qos.logback.core.LayoutBase.

I create a thread-local variable to store the reference to the method org.springframework.transaction.support.TransactionSynchronizationManager.isActualTransactionActive(). Whenever a new log line is printed out, getSpringTransactionInfo() is called and it returns a one-character string that will go into the log.

References:

• Tips for Debugging Spring's @Transactional Annotation
• org.springframework.transaction.support.TransactionSynchronizationManager
• java.lang.ThreadLocal
• java.lang.Class.getMethod()

Code:

private static ThreadLocal txCheckMethod;

private static String getSpringTransactionInfo() {
    if (txCheckMethod == null) {
        txCheckMethod = new ThreadLocal() {
            @Override public Method initialValue() {           
                try {
                    ClassLoader contextClassLoader = Thread.currentThread().getContextClassLoader();
                    Class tsmClass = contextClassLoader.loadClass("org.springframework.transaction.support.TransactionSynchronizationManager");
                    return tsmClass.getMethod("isActualTransactionActive", (Class[])null);
                } catch (Exception e) {
                    e.printStackTrace();
                    return null;
                }                      
            }
         };    
    }
    assert txCheckMethod != null;
    Method m = txCheckMethod.get();
    String res;
    if (m == null) {
        res = " "; // there is no Spring here
    }
    else {
        Boolean isActive = null;
        try {
            isActive = (Boolean) m.invoke((Object)null);
            if (isActive) {
                res = "T"; // transaction active                    
            }
            else {
                res = "~"; // transaction inactive
            }
        }
        catch (Exception exe) {
            // suppress 
            res = "?";
        }
    }
    return res;
}