JDK10 - XML mapper can not be found

[dawwin]

I was testing mybatis with JDK10 and I found an issue with named modules. If I want to use xml mapper files then I have to use opens and open mapper package to ALL other modules. Opening for java.base and mybatis doesn't solve the case. It seems like mybatis can't find this file and assumes that it's not there. I tried debugging it, but I ended up in AppClassLoader from java.base which tries to load xml file, but it can't find it. However as I mentioned, adding java.base doesn't help.

MyBatis version

3.4.6, but probably the problem occurs on any version

Database vendor and version

Any

Test case or example project

https://github.com/dawwin/mybatis.jdk10test

Steps to reproduce

Replace opens dwd.mybatisjdk10test.mapper with opens dwd.mybatisjdk10test.mapper to java.base, mybatis; in module-info.java, then run Application.java

Expected result

Successful insert and select calls to database in TestService.runTests(). MyBatis should work with XML files on JDK10 without exposing mapper packages to all other modules.

Actual result

org.apache.ibatis.binding.BindingException: Invalid bound statement (not found): dwd.mybatisjdk10test.mapper.UserMapper.saveAll
at mybatis@3.5.0-SNAPSHOT/org.apache.ibatis.binding.MapperMethod$SqlCommand.(MapperMethod.java:232) ~[mybatis-3.5.0-SNAPSHOT.jar:na]
at mybatis@3.5.0-SNAPSHOT/org.apache.ibatis.binding.MapperMethod.(MapperMethod.java:50) ~[mybatis-3.5.0-SNAPSHOT.jar:na]
at mybatis@3.5.0-SNAPSHOT/org.apache.ibatis.binding.MapperProxy.lambda$cachedMapperMethod$0(MapperProxy.java:62) ~[mybatis-3.5.0-SNAPSHOT.jar:na]
at java.base/java.util.concurrent.ConcurrentHashMap.computeIfAbsent(ConcurrentHashMap.java:1719) ~[na:na]
at mybatis@3.5.0-SNAPSHOT/org.apache.ibatis.binding.MapperProxy.cachedMapperMethod(MapperProxy.java:62) ~[mybatis-3.5.0-SNAPSHOT.jar:na]
at mybatis@3.5.0-SNAPSHOT/org.apache.ibatis.binding.MapperProxy.invoke(MapperProxy.java:57) ~[mybatis-3.5.0-SNAPSHOT.jar:na]
at jdk.proxy2/com.sun.proxy.jdk.proxy2.$Proxy49.saveAll(Unknown Source) ~[na:na]
at dwd.mybatis.jdk10test/dwd.mybatisjdk10test.service.TestService.runTests(TestService.java:33) ~[classes/:na]

[harawata]

Thank you, @dawwin !

Currently, MyBatis loads XML mapper file using ClassLoader#getResourceAsStream().
As the javadoc says, the mapper package has to be opened 'unconditionally' when the XML file is in a named module.

this method will only find resources in packages of named modules when the package is opened unconditionally.

I plan to change the implementation to use Class#getResourceAsStream().
With this method, the mapper package needs to be opened only to 'mybatis'.

[harawata]

I've committed the change.
Let me know if there is any problem!

Note that the package must be fully open when loading XML mapper directly (i.e. without Java interface).

<mapper resource="com/example/mapper/Mapper.xml" />

[Shashwatsingh22]

Once, also check that you have added your module (where your mapper present) to pom.xml file where mybatis-config.xml file present