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Spring log query execution time for SimpleJdbcTemplate

Without going into too much depth here is the way to do it. The challenge faced were SimpleJdbcTemplate has a no-arg constructor. In future the intent of this interceptor is to detect N+1 query problem by using a light weight instrumentation framework plugged in instead of logging query times in log file.

 public void setDataSource(DataSource dataSource) {
  final SimpleJdbcTemplate simpleJdbcTemplate = new SimpleJdbcTemplate(
  Enhancer enhancer = new Enhancer();
  enhancer.setCallback(new MethodInterceptor() {
   public Object intercept(Object obj, Method method,
     Object[] args, MethodProxy proxy) throws Throwable {
     String methodName = method.getName();
     if (methodName.startsWith("query")
       || methodName.startsWith("batchUpdate")
       || methodName.startsWith("update")) {
      String query = (String) args[0];
      String prefix = extractQueryName(query);
      long start = System.currentTimeMillis();
      Object result = method.invoke(simpleJdbcTemplate,
        args);"Query {} took {} msec", prefix,
        (System.currentTimeMillis() - start));
      return result;
     } else {
      return method.invoke(simpleJdbcTemplate, args);
    } catch(InvocationTargetException e) {
     throw e.getTargetException();

   private String extractQueryName(String query) {
    //with xml based property files I am externalizing queries into a xml file and then when reading them back I am appending query name as a comment before qeury so a query look like below and I extract query name here.
    /*getPerson*/ select * from person
  this.jdbcTemplate = (SimpleJdbcTemplate) enhancer.create(new Class[]{DataSource.class}, new Object[]{dataSource});


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