Avoid corner case NPE when setting a parameter

Author: harawata

src/main/java/org/apache/ibatis/scripting/defaults/DefaultParameterHandler.java

@@ -166,6 +166,10 @@ public void setParameters(PreparedStatement ps) {
           if (typeHandler == null) {
             typeHandler = typeHandlerRegistry.getTypeHandler(actualJdbcType);
           }
+          if (typeHandler == null) {
+            throw new TypeException("Could not find type handler for Java type '" + propertyGenericType.getTypeName()
+                + "' nor JDBC type '" + actualJdbcType + "'");
+          }
           try {
             typeHandler.setParameter(ps, i + 1, value, jdbcType);
           } catch (TypeException | SQLException e) {

src/test/java/org/apache/ibatis/submitted/typehandler/Mapper.java

@@ -21,6 +21,7 @@
 import org.apache.ibatis.annotations.ConstructorArgs;
 import org.apache.ibatis.annotations.Insert;
 import org.apache.ibatis.annotations.Options;
+import org.apache.ibatis.annotations.Param;
 import org.apache.ibatis.annotations.Result;
 import org.apache.ibatis.annotations.Results;
 import org.apache.ibatis.annotations.Select;
@@ -66,4 +67,7 @@ public interface Mapper {
 
   @Select("select id, name, released_on from product where id = #{id}")
   Map<String, Object> getProductAsMap(Integer id);
+
+  @Insert({ "insert into vague (vague) values (#{bean})" })
+  int insertVague(@Param("bean") VagueBean bean);
 }

src/test/java/org/apache/ibatis/submitted/typehandler/TypeHandlerTest.java

@@ -15,8 +15,10 @@
  */
 package org.apache.ibatis.submitted.typehandler;
 
+import static org.assertj.core.api.Assertions.assertThat;
 import static org.junit.jupiter.api.Assertions.assertEquals;
 import static org.junit.jupiter.api.Assertions.assertNotNull;
+import static org.junit.jupiter.api.Assertions.fail;
 
 import java.io.Reader;
 import java.sql.Time;
@@ -36,6 +38,7 @@
 import org.apache.ibatis.submitted.typehandler.Product.ProductIdTypeHandler;
 import org.apache.ibatis.type.JdbcType;
 import org.apache.ibatis.type.LocalDateTypeHandler;
+import org.apache.ibatis.type.TypeException;
 import org.junit.jupiter.api.BeforeEach;
 import org.junit.jupiter.api.Test;
 
@@ -202,4 +205,17 @@ void shouldHandlerBePickedBasedOnRuntimeJdbcType_Map() {
     }
   }
 
+  @Test
+  void shouldThrowProperExceptionWhenNoHandlerFoundForParam() {
+    addMapper();
+    try (SqlSession sqlSession = sqlSessionFactory.openSession()) {
+      Mapper mapper = sqlSession.getMapper(Mapper.class);
+      mapper.insertVague(new VagueBean());
+      fail("Should throw exception");
+    } catch (Exception e) {
+      assertThat(e).cause().isExactlyInstanceOf(TypeException.class).hasMessage(
+          "Could not find type handler for Java type '" + VagueBean.class.getName() + "' nor JDBC type 'OTHER'");
+    }
+  }
+
 }

src/test/java/org/apache/ibatis/submitted/typehandler/VagueBean.java

@@ -0,0 +1,40 @@
+/*
+ *    Copyright 2009-2025 the original author or authors.
+ *
+ *    Licensed under the Apache License, Version 2.0 (the "License");
+ *    you may not use this file except in compliance with the License.
+ *    You may obtain a copy of the License at
+ *
+ *       https://www.apache.org/licenses/LICENSE-2.0
+ *
+ *    Unless required by applicable law or agreed to in writing, software
+ *    distributed under the License is distributed on an "AS IS" BASIS,
+ *    WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ *    See the License for the specific language governing permissions and
+ *    limitations under the License.
+ */
+
+package org.apache.ibatis.submitted.typehandler;
+
+import java.util.Set;
+
+public class VagueBean {
+  private Integer id;
+  private Set<?> vague;
+
+  public Integer getId() {
+    return id;
+  }
+
+  public void setId(Integer id) {
+    this.id = id;
+  }
+
+  public Set<?> getVague() {
+    return vague;
+  }
+
+  public void setVague(Set<?> vague) {
+    this.vague = vague;
+  }
+}

src/test/resources/org/apache/ibatis/submitted/typehandler/CreateDB.sql

@@ -16,6 +16,7 @@
 
 drop table users if exists;
 drop table product if exists;
+drop table vague if exists;
 
 create table users (
   id int,
@@ -30,8 +31,15 @@ create table product (
   released_on date
 );
 
+create table vague (
+  id int identity,
+  vague other
+);
+
 insert into users (id, name, city, state) values(1, '   User1', '  Carmel  ', '  IN ');
 
 insert into product (id, name, released_on) values
 (1, 'iPod', '2001-11-10'),
 (2, 'iPad', '2010-04-03');
+
+insert into vague (id, vague) values (1, null);