add_stacktrace_in_monitor (#181)

* add_stacktrace_in_monitor

* Add LegacySpringBanUtil

---------

Co-authored-by: “HzjNeverStop” <“441627022@qq.com”>

src/main/java/com/alipay/sofa/common/utils/CharsetUtil.java

@@ -98,8 +98,8 @@ public static void checkUTF8WellFormed(byte[] bytes, int off, int len, int mode)
                 case MODE_ASSERT:
                     throw new IllegalArgumentException("Input byte array is not well formed utf-8");
                 case MODE_MONITOR:
-                    CHARSET_MONITOR_LOG.error("Detect not well formed utf-8 input: {}", new String(
-                        bytes, off, len, StandardCharsets.UTF_8));
+                    CHARSET_MONITOR_LOG.error("Detect not well formed utf-8 input: {}, trace:{}",
+                        new String(bytes, off, len, StandardCharsets.UTF_8), currentStackTrace());
                 default:
             }
         }
@@ -199,4 +199,15 @@ private static boolean isWellFormedSlowPath(byte[] bytes, int off, int end) {
             }
         }
     }
+
+    private static String currentStackTrace() {
+        StringBuilder sb = new StringBuilder();
+        sb.append("\n");
+        StackTraceElement[] stackTraceElements = Thread.currentThread().getStackTrace();
+        // 5 means the caller method
+        for (int i = 5; i < stackTraceElements.length; i++) {
+            sb.append("    ").append(stackTraceElements[i]).append("\n");
+        }
+        return sb.toString();
+    }
 }