Spring mvc plugin auto add '/' if necessary (#1315)

* spring mvc plugin auto add '/' if necessary

apm-sniffer/apm-sdk-plugin/spring-plugins/mvc-annotation-4.x-plugin/src/test/java/org/apache/skywalking/apm/plugin/spring/mvc/v4/ControllerConstructorInterceptorTest.java

@@ -54,7 +54,7 @@ public class ControllerConstructorInterceptorTest {
         Method m = obj.getClass().getMethods()[0];
         cache.addPathMapping(m, "#toString");
 
-        Assert.assertEquals("the two value should be equal", cache.findPathMapping(m), "/test1#toString");
+        Assert.assertEquals("the two value should be equal", cache.findPathMapping(m), "/test1/#toString");
     }
 
     @Test
@@ -67,7 +67,7 @@ public class ControllerConstructorInterceptorTest {
         Method m = obj.getClass().getMethods()[0];
         cache.addPathMapping(m, "#toString");
 
-        Assert.assertEquals("the two value should be equal", cache.findPathMapping(m), "#toString");
+        Assert.assertEquals("the two value should be equal", cache.findPathMapping(m), "/#toString");
     }
 
     @Test
@@ -80,7 +80,7 @@ public class ControllerConstructorInterceptorTest {
         Method m = obj.getClass().getMethods()[0];
         cache.addPathMapping(m, "#toString");
 
-        Assert.assertEquals("the two value should be equal", cache.findPathMapping(m), "/test3#toString");
+        Assert.assertEquals("the two value should be equal", cache.findPathMapping(m), "/test3/#toString");
     }
 
     @RequestMapping(value = "/test1")

apm-sniffer/apm-sdk-plugin/spring-plugins/mvc-annotation-4.x-plugin/src/test/java/org/apache/skywalking/apm/plugin/spring/mvc/v4/PathMappingCacheTest.java

@@ -45,7 +45,31 @@ public class PathMappingCacheTest {
         Method m = obj.getClass().getMethods()[0];
         pathMappingCache.addPathMapping(m, "#toString");
 
-        Assert.assertEquals("the two value should be equal", pathMappingCache.findPathMapping(m), "org.apache.skywalking.apm.plugin.spring.mvc#toString");
+        Assert.assertEquals("the two value should be equal", pathMappingCache.findPathMapping(m), "/org.apache.skywalking.apm.plugin.spring.mvc/#toString");
 
     }
+
+    @Test
+    public void testAutoAddPathSeparator() {
+        String rightPath = "/root/sub";
+
+        Object obj = new Object();
+        Method m = obj.getClass().getMethods()[0];
+
+        PathMappingCache cache = new PathMappingCache("root");
+        cache.addPathMapping(m, "sub");
+        Assert.assertEquals(cache.findPathMapping(m), rightPath);
+
+        PathMappingCache cache2 = new PathMappingCache("/root");
+        cache2.addPathMapping(m, "/sub");
+        Assert.assertEquals(cache2.findPathMapping(m), rightPath);
+
+        PathMappingCache cache3 = new PathMappingCache("root");
+        cache3.addPathMapping(m, "/sub");
+        Assert.assertEquals(cache3.findPathMapping(m), rightPath);
+
+        PathMappingCache cache4 = new PathMappingCache("/root");
+        cache4.addPathMapping(m, "sub");
+        Assert.assertEquals(cache4.findPathMapping(m), rightPath);
+    }
 }

apm-sniffer/apm-sdk-plugin/spring-plugins/mvc-annotation-commons/src/main/java/org/apache/skywalking/apm/plugin/spring/mvc/commons/PathMappingCache.java

@@ -19,6 +19,8 @@
 
 package org.apache.skywalking.apm.plugin.spring.mvc.commons;
 
+import org.apache.skywalking.apm.util.StringUtil;
+
 import java.lang.reflect.Method;
 import java.util.concurrent.ConcurrentHashMap;
 
@@ -28,11 +30,17 @@ import java.util.concurrent.ConcurrentHashMap;
  * @author zhangxin
  */
 public class PathMappingCache {
+
+    private static final String PATH_SEPARATOR = "/";
+
     private String classPath = "";
 
     private ConcurrentHashMap<Method, String> methodPathMapping = new ConcurrentHashMap<Method, String>();
 
     public PathMappingCache(String classPath) {
+        if (!StringUtil.isEmpty(classPath) && !classPath.startsWith(PATH_SEPARATOR)) {
+            classPath = PATH_SEPARATOR + classPath;
+        }
         this.classPath = classPath;
     }
 
@@ -41,6 +49,10 @@ public class PathMappingCache {
     }
 
     public void addPathMapping(Method method, String methodPath) {
+        if (!StringUtil.isEmpty(methodPath) && !methodPath.startsWith(PATH_SEPARATOR)
+                && !classPath.endsWith(PATH_SEPARATOR)) {
+            methodPath = PATH_SEPARATOR + methodPath;
+        }
         methodPathMapping.put(method, classPath + methodPath);
     }
 }