diff --git a/apm-commons/apm-trace/src/main/java/org/skywalking/apm/trace/tag/AbstractTag.java b/apm-commons/apm-trace/src/main/java/org/skywalking/apm/trace/tag/AbstractTag.java
index 1ded62e9824f8e1c58ebe637098d7f968eb1fff3..cc37ea86be41d26f33ec0196e4132811489254af 100644
--- a/apm-commons/apm-trace/src/main/java/org/skywalking/apm/trace/tag/AbstractTag.java
+++ b/apm-commons/apm-trace/src/main/java/org/skywalking/apm/trace/tag/AbstractTag.java
@@ -30,6 +30,4 @@ public abstract class AbstractTag<T> {
     public String key() {
         return this.key;
     }
-
-    public abstract T get(Span span);
 }
diff --git a/apm-commons/apm-trace/src/main/java/org/skywalking/apm/trace/tag/BooleanTag.java b/apm-commons/apm-trace/src/main/java/org/skywalking/apm/trace/tag/BooleanTag.java
index a08d50e5736d341815dd183de76a66f35740e7e9..0b9e091d7a614be83c73040a7edabb4a14cca2d8 100644
--- a/apm-commons/apm-trace/src/main/java/org/skywalking/apm/trace/tag/BooleanTag.java
+++ b/apm-commons/apm-trace/src/main/java/org/skywalking/apm/trace/tag/BooleanTag.java
@@ -21,20 +21,7 @@ public class BooleanTag extends AbstractTag<Boolean> {
         span.setTag(key, tagValue);
     }
 
-    /**
-     * Get a tag value, type of {@link Boolean}. After akka-message/serialize, all tags values are type of {@link
-     * String}, convert to {@link Boolean}, if necessary.
-     *
-     * @param span
-     * @return tag value
-     */
-    @Override
-    public Boolean get(Span span) {
-        Boolean tagValue = span.getBoolTag(super.key);
-        if (tagValue == null) {
-            return defaultValue;
-        } else {
-            return tagValue;
-        }
+    public boolean defaultValue() {
+        return this.defaultValue;
     }
 }
diff --git a/apm-commons/apm-trace/src/main/java/org/skywalking/apm/trace/tag/IntTag.java b/apm-commons/apm-trace/src/main/java/org/skywalking/apm/trace/tag/IntTag.java
index e02e7e580403f70c936ded7acb4fe46a1f660ef5..7261cc3501d909d8c178aca84052f8e038bffcb7 100644
--- a/apm-commons/apm-trace/src/main/java/org/skywalking/apm/trace/tag/IntTag.java
+++ b/apm-commons/apm-trace/src/main/java/org/skywalking/apm/trace/tag/IntTag.java
@@ -16,21 +16,4 @@ public class IntTag extends AbstractTag<Integer> {
     public void set(Span span, Integer tagValue) {
         span.setTag(super.key, tagValue);
     }
-
-    /**
-     * Get a tag value, type of {@link Integer}. After akka-message/serialize, all tags values are type of {@link
-     * String}, convert to {@link Integer}, if necessary.
-     *
-     * @param span
-     * @return tag value
-     */
-    @Override
-    public Integer get(Span span) {
-        Integer tagValue = span.getIntTag(super.key);
-        if (tagValue == null) {
-            return null;
-        } else {
-            return tagValue;
-        }
-    }
 }
diff --git a/apm-commons/apm-trace/src/main/java/org/skywalking/apm/trace/tag/StringTag.java b/apm-commons/apm-trace/src/main/java/org/skywalking/apm/trace/tag/StringTag.java
index 1fa32f7ce67b873704f4a2408d8ec5812a949c17..1ce53d5dd9dffa5acbcffae93138a54bd82ebf5f 100644
--- a/apm-commons/apm-trace/src/main/java/org/skywalking/apm/trace/tag/StringTag.java
+++ b/apm-commons/apm-trace/src/main/java/org/skywalking/apm/trace/tag/StringTag.java
@@ -17,9 +17,4 @@ public class StringTag extends AbstractTag<String> {
     public void set(Span span, String tagValue) {
         span.setTag(key, tagValue);
     }
-
-    @Override
-    public String get(Span span) {
-        return span.getStrTag(super.key);
-    }
 }
diff --git a/apm-sniffer/apm-sniffer-mock/src/main/java/org/skywalking/apm/sniffer/mock/trace/tag/BooleanTagGetter.java b/apm-sniffer/apm-sniffer-mock/src/main/java/org/skywalking/apm/sniffer/mock/trace/tag/BooleanTagGetter.java
index 391c7159445ba8685388258cf8ba27a0f18dda3d..7e2f89f15c782fc86f33a185b0b026dff9f98f89 100644
--- a/apm-sniffer/apm-sniffer-mock/src/main/java/org/skywalking/apm/sniffer/mock/trace/tag/BooleanTagGetter.java
+++ b/apm-sniffer/apm-sniffer-mock/src/main/java/org/skywalking/apm/sniffer/mock/trace/tag/BooleanTagGetter.java
@@ -10,6 +10,11 @@ import org.skywalking.apm.trace.tag.BooleanTag;
  */
 public class BooleanTagGetter {
     public static Boolean get(Span span, BooleanTag tag) {
-        return span.getBoolTag(tag.key());
+        Boolean tagValue = span.getBoolTag(tag.key());
+        if (tagValue == null) {
+            return tag.defaultValue();
+        } else {
+            return tagValue;
+        }
     }
 }
diff --git a/apm-sniffer/apm-sniffer-mock/src/main/java/org/skywalking/apm/sniffer/mock/trace/tag/IntTagGetter.java b/apm-sniffer/apm-sniffer-mock/src/main/java/org/skywalking/apm/sniffer/mock/trace/tag/IntTagGetter.java
index 43d0b1c19e870914a2c172eefd78f4066f2d685f..04e5bb5f0b6a3bceb1ec0cc3c44f8f73d9637069 100644
--- a/apm-sniffer/apm-sniffer-mock/src/main/java/org/skywalking/apm/sniffer/mock/trace/tag/IntTagGetter.java
+++ b/apm-sniffer/apm-sniffer-mock/src/main/java/org/skywalking/apm/sniffer/mock/trace/tag/IntTagGetter.java
@@ -10,6 +10,11 @@ import org.skywalking.apm.trace.tag.IntTag;
  */
 public class IntTagGetter {
     public static Integer get(Span span, IntTag tag) {
-        return span.getIntTag(tag.key());
+        Integer tagValue = span.getIntTag(tag.key());
+        if (tagValue == null) {
+            return null;
+        } else {
+            return tagValue;
+        }
     }
 }