diff --git a/testable-core/src/main/java/com/alibaba/testable/core/tool/OmniConstructor.java b/testable-core/src/main/java/com/alibaba/testable/core/tool/OmniConstructor.java
index bd8ee1f..23a58b5 100644
--- a/testable-core/src/main/java/com/alibaba/testable/core/tool/OmniConstructor.java
+++ b/testable-core/src/main/java/com/alibaba/testable/core/tool/OmniConstructor.java
@@ -3,6 +3,7 @@ package com.alibaba.testable.core.tool;
 import com.alibaba.testable.core.model.Null;
 import com.alibaba.testable.core.util.TypeUtil;
 
+import java.lang.reflect.Array;
 import java.lang.reflect.Constructor;
 import java.lang.reflect.Field;
 import java.lang.reflect.InvocationTargetException;
@@ -13,39 +14,14 @@ import java.lang.reflect.InvocationTargetException;
 public class OmniConstructor {
 
     public static <T> T newInstance(Class<T> clazz) {
-        return newInstance(clazz, isJavaAgentEnabled(clazz));
-    }
-
-    public static <T> void appendInstance(Object target, Class<T> clazz) {
-        return;
-    }
-
-    public static <T> void appendInstance(Object target, int count, Class<T> clazz) {
-        return;
-    }
-
-    private static boolean isJavaAgentEnabled(Class<?> clazz) {
         try {
-            clazz.getDeclaredConstructor(Null.class);
-        } catch (NoSuchMethodException e) {
-            return false;
-        }
-        return true;
-    }
-
-    private static <T> T newInstance(Class<T> clazz, boolean withJavaAgent) {
-        try {
-            Constructor<?> constructor = withJavaAgent ?
-                clazz.getDeclaredConstructor(Null.class) : clazz.getDeclaredConstructor();
-            constructor.setAccessible(true);
-            Object ins = withJavaAgent ? constructor.newInstance(new Null()) : constructor.newInstance();
-            for (Field f : TypeUtil.getAllFields(clazz)) {
-                f.setAccessible(true);
-                if (!f.getType().isPrimitive()) {
-                    f.set(ins, newInstance(f.getType(), withJavaAgent));
-                }
+            if (clazz.isPrimitive()) {
+                return newPrimitive(clazz);
+            } else if (clazz.isArray()) {
+                return newArray(clazz);
+            } else {
+                return newObject(clazz);
             }
-            return (T)ins;
         } catch (NoSuchMethodException e) {
             return null;
         } catch (IllegalAccessException e) {
@@ -57,4 +33,87 @@ public class OmniConstructor {
         }
     }
 
+    public static <T> void appendInstance(Object target, Class<T> clazz) {
+        appendInstance(target, 1, clazz);
+    }
+
+    public static <T> void appendInstance(Object target, int count, Class<T> clazz) {
+        return;
+    }
+
+    private static <T> T newObject(Class<T> clazz)
+        throws NoSuchMethodException, IllegalAccessException, InvocationTargetException, InstantiationException {
+        Constructor<?> constructor = getBestConstructor(clazz);
+        constructor.setAccessible(true);
+        Object ins = newInstance(constructor);
+        for (Field f : TypeUtil.getAllFields(clazz)) {
+            f.setAccessible(true);
+            f.set(ins, newInstance(f.getType()));
+        }
+        return (T)ins;
+    }
+
+    private static <T> T newArray(Class<T> clazz) {
+        return (T)Array.newInstance(clazz.getComponentType(), 0);
+    }
+
+    private static <T> T newPrimitive(Class<T> clazz) {
+        if (clazz.equals(int.class)) {
+            return (T)Integer.valueOf(0);
+        } else if (clazz.equals(char.class)) {
+            return (T)Character.valueOf((char)0);
+        } else if (clazz.equals(short.class)) {
+            return (T)Short.valueOf((short)0);
+        } else if (clazz.equals(long.class)) {
+            return (T)Long.valueOf(0L);
+        } else if (clazz.equals(double.class)) {
+            return (T)Double.valueOf(0);
+        } else if (clazz.equals(float.class)) {
+            return (T)Float.valueOf(0F);
+        } else if (clazz.equals(byte.class)) {
+            return (T)Byte.valueOf((byte)0);
+        } else if (clazz.equals(boolean.class)) {
+            return (T)Boolean.valueOf(false);
+        }
+        return null;
+    }
+
+    private static boolean isJavaAgentEnabled(Class<?> clazz) {
+        try {
+            clazz.getDeclaredConstructor(Null.class);
+        } catch (NoSuchMethodException e) {
+            return false;
+        }
+        return true;
+    }
+
+    private static Object newInstance(Constructor<?> constructor)
+        throws InstantiationException, IllegalAccessException, InvocationTargetException {
+        Class<?>[] types = constructor.getParameterTypes();
+        if (types.length == 1 && types[0].equals(Null.class)) {
+            return constructor.newInstance(new Null());
+        } else {
+            Object[] args = new Object[types.length];
+            for (int i = 0; i < types.length; i++) {
+                args[i] = newInstance(types[i]);
+            }
+            return constructor.newInstance(args);
+        }
+    }
+
+    private static Constructor<?> getBestConstructor(Class<?> clazz) throws NoSuchMethodException {
+        Constructor<?> bestConstructor = null;
+        int minimalParametersSize = 999;
+        for (Constructor<?> constructor : clazz.getDeclaredConstructors()) {
+            Class<?>[] types = constructor.getParameterTypes();
+            if (types.length == 1 && types[0].equals(Null.class)) {
+                return constructor;
+            } else if (types.length < minimalParametersSize) {
+                minimalParametersSize = types.length;
+                bestConstructor = constructor;
+            }
+        }
+        return bestConstructor;
+    }
+
 }
diff --git a/testable-core/src/test/java/com/alibaba/testable/core/tool/OmniAccessorTest.java b/testable-core/src/test/java/com/alibaba/testable/core/tool/OmniAccessorTest.java
index 546df63..e4f8e93 100644
--- a/testable-core/src/test/java/com/alibaba/testable/core/tool/OmniAccessorTest.java
+++ b/testable-core/src/test/java/com/alibaba/testable/core/tool/OmniAccessorTest.java
@@ -76,7 +76,7 @@ class OmniAccessorTest {
         DemoParent parent = prepareDemoObject();
         Object obj = PrivateAccessor.<String>invokeStatic(OmniAccessor.class, "getByPath", parent, "c{DemoChild}/gc{DemoGrandChild}", "c/gc");
         assertTrue(obj instanceof DemoGrandChild);
-        assertEquals(1, PrivateAccessor.<Integer>get(obj, "i"));
+        assertEquals(0, PrivateAccessor.<Integer>get(obj, "i"));
     }
 
     @Test
@@ -87,12 +87,7 @@ class OmniAccessorTest {
     }
 
     private DemoParent prepareDemoObject() {
-        DemoParent parent = new DemoParent();
-        DemoChild child = new DemoChild();
-        DemoGrandChild grandChild = new DemoGrandChild(1);
-        PrivateAccessor.set(parent, "c", child);
-        PrivateAccessor.set(child, "gc", grandChild);
-        return parent;
+        return OmniConstructor.newInstance(DemoParent.class);
     }
 
 }