From df620103579cea31934dad311d3dd60ea810af5f Mon Sep 17 00:00:00 2001
From: sanxun0325 <bbz17640380550.com>
Date: Fri, 3 Dec 2021 23:20:19 +0800
Subject: [PATCH] support java integer null

---
 codec.go                                      |  6 +++++-
 int.go                                        |  3 +++
 int_test.go                                   |  1 +
 object_test.go                                | 19 ++++++++++++++++++
 .../src/main/java/test/TestCustomReply.java   | 20 +++++++++++++++++++
 .../src/main/java/test/model/User.java        | 18 +++++++++++++++++
 6 files changed, 66 insertions(+), 1 deletion(-)

diff --git a/codec.go b/codec.go
index 425468c9..2055a12c 100644
--- a/codec.go
+++ b/codec.go
@@ -455,7 +455,11 @@ func ConvertSliceValueType(destTyp reflect.Type, v reflect.Value) (reflect.Value
 		if cv, ok := item.(reflect.Value); ok {
 			itemValue = cv
 		} else {
-			itemValue = reflect.ValueOf(item)
+			if item == nil {
+				itemValue = reflect.Zero(destTyp.Elem())
+			} else {
+				itemValue = reflect.ValueOf(item)
+			}
 		}
 
 		if !elemPtrType && itemValue.Kind() == reflect.Ptr {
diff --git a/int.go b/int.go
index dd06d11a..06cdb719 100644
--- a/int.go
+++ b/int.go
@@ -102,6 +102,9 @@ func (d *Decoder) decInt32(flag int32) (int32, error) {
 		err = binary.Read(d.reader, binary.BigEndian, &i32)
 		return i32, perrors.WithStack(err)
 
+	case tag == BC_NULL:
+		return int32(0), nil
+
 	default:
 		return 0, perrors.Errorf("decInt32 integer wrong tag:%#x", tag)
 	}
diff --git a/int_test.go b/int_test.go
index 0c98ff6f..441bca36 100644
--- a/int_test.go
+++ b/int_test.go
@@ -116,6 +116,7 @@ func TestEncInt32Len4B(t *testing.T) {
 }
 
 func TestInt(t *testing.T) {
+	testDecodeFramework(t, "replyNull", nil)
 	testDecodeFramework(t, "replyInt_0", int32(0))
 	testDecodeFramework(t, "replyInt_0x30", int32(0x30))
 	testDecodeFramework(t, "replyInt_0x3ffff", int32(0x3ffff))
diff --git a/object_test.go b/object_test.go
index f2d1e4f3..d6d67b19 100644
--- a/object_test.go
+++ b/object_test.go
@@ -897,3 +897,22 @@ func TestWrapperClassArray(t *testing.T) {
 	da := &DoubleArray{Values: []float64{1.0, 100.0, 10000.1}}
 	assert.True(t, reflect.DeepEqual(got, da))
 }
+
+type User struct {
+	Id   int32
+	List []int32
+}
+
+func (u *User) JavaClassName() string {
+	return "test.model.User"
+}
+
+func TestDecodeIntegerHasNull(t *testing.T) {
+	RegisterPOJO(&User{})
+	testDecodeFramework(t, "customReplyTypedIntegerHasNull", &User{Id: 0})
+}
+
+func TestDecodeSliceIntegerHasNull(t *testing.T) {
+	RegisterPOJO(&User{})
+	testDecodeFramework(t, "customReplyTypedListIntegerHasNull", &User{Id: 0, List: []int32{1, 0}})
+}
diff --git a/test_hessian/src/main/java/test/TestCustomReply.java b/test_hessian/src/main/java/test/TestCustomReply.java
index 3ae19de9..8d22362e 100644
--- a/test_hessian/src/main/java/test/TestCustomReply.java
+++ b/test_hessian/src/main/java/test/TestCustomReply.java
@@ -22,10 +22,12 @@
 import com.alibaba.fastjson.JSONObject;
 import com.caucho.hessian.test.A0;
 import com.caucho.hessian.test.A1;
+import com.caucho.hessian.test.TestObject;
 import test.generic.BusinessData;
 import test.generic.Response;
 import test.model.CustomMap;
 import test.model.DateDemo;
+import test.model.User;
 
 import java.io.OutputStream;
 import java.io.Serializable;
@@ -92,6 +94,24 @@ public void customReplyJsonString() throws Exception {
         output.flush();
     }
 
+    public void customReplyTypedIntegerHasNull() throws Exception {
+        User user = new User();
+        user.setId(null);
+        output.writeObject(user);
+        output.flush();
+    }
+
+    public void customReplyTypedListIntegerHasNull() throws Exception {
+        User user = new User();
+        user.setId(null);
+        List<Integer> list = new ArrayList<>();
+        list.add(1);
+        list.add(null);
+        user.setList(list);
+        output.writeObject(user);
+        output.flush();
+    }
+
     public void customReplyTypedFixedListHasNull() throws Exception {
         Object[] o = new Object[]{new A0(), new A1(), null};
         output.writeObject(o);
diff --git a/test_hessian/src/main/java/test/model/User.java b/test_hessian/src/main/java/test/model/User.java
index a9f5e523..2a0538a3 100644
--- a/test_hessian/src/main/java/test/model/User.java
+++ b/test_hessian/src/main/java/test/model/User.java
@@ -18,10 +18,15 @@
 package test.model;
 
 import java.io.Serializable;
+import java.util.List;
 
 public class User implements Serializable {
     private String name;
 
+    private Integer id;
+
+    private List<Integer> list;
+
     public User() {
     }
 
@@ -37,10 +42,23 @@ public void setName(String name) {
         this.name = name;
     }
 
+    public Integer getId() {
+        return id;
+    }
+
+    public void setId(Integer id) {
+        this.id = id;
+    }
+
+    public List<Integer> getList() { return list; }
+
+    public void setList(List<Integer> list) {  this.list = list; }
+
     @Override
     public String toString() {
         return "User{" +
                 "name='" + name + '\'' +
+                "id='" + id + '\'' +
                 '}';
     }
 }