fix NPE

mooctest-user-server/src/main/java/cn/iselab/mooctest/user/web/wrapper/BaseWrapper.java

@@ -7,6 +7,7 @@ import org.springframework.data.domain.PageImpl;
 import org.springframework.data.domain.PageRequest;
 
 import java.util.List;
+import java.util.Objects;
 import java.util.stream.Collectors;
 
 /**
@@ -22,7 +23,7 @@ public abstract class BaseWrapper<VO, DATA> {
     public abstract DATA unwrap(VO data);
 
     public List<VO> wrap(List<DATA> data) {
-        return data.stream().map(this::wrap).collect(Collectors.toList());
+        return data.stream().filter(Objects::nonNull).map(this::wrap).collect(Collectors.toList());
     }
 
     public Page<VO> wrap(Page<DATA> data) {

mooctest-user-server/src/test/java/cn/iselab/mooctest/user/web/wrapper/UserWrapperTest.java

@@ -0,0 +1,39 @@
+package cn.iselab.mooctest.user.web.wrapper;
+
+import cn.iselab.mooctest.rpc.user.data.UserDTO;
+import cn.iselab.mooctest.user.model.User;
+import com.google.common.collect.Lists;
+import org.junit.Test;
+import org.mockito.InjectMocks;
+
+import java.sql.Timestamp;
+import java.util.List;
+
+import static org.junit.Assert.*;
+
+/**
+ * @program: mooctest-user
+ * @mail: menduo96@gmail.com
+ * @author: menduo
+ * @create: 2019-12-04 14:34
+ **/
+public class UserWrapperTest {
+    @InjectMocks
+    private UserWrapper userWrapper = new UserWrapper();
+
+    @Test
+    public void test_wrap_if_data_content_null() {
+        User user1 = new User();
+        user1.setId(1L);
+        user1.setCreateTime(new Timestamp(System.currentTimeMillis()));
+        User user2 = new User();
+        user2.setId(2L);
+        user2.setCreateTime(new Timestamp(System.currentTimeMillis()));
+        User user3 = null;
+
+        List<User> users = Lists.newArrayList(user1, user2, user3);
+        List<UserDTO> userDTOS = userWrapper.wrap(users);
+        assertEquals(users.size(),3);
+        assertEquals(userDTOS.size(),2);
+    }
+}