A demo using MyBatis and JPA to access Manticore Search

Prerequisite

1. OpenJDK 17+
2. set mysql_version_string = 5.0.37 according to Notes on MySQL connectors.

Create an index in Manticore

Connect to Manticore using the MySQL client.

Run

mysql -P9306 -h127.0.0.1

Execute the following SQL statement to create the index 'testrt'.

CREATE TABLE testrt (title TEXT, content TEXT, gid INT);

Run the test

mvnw test

The test passed.

But you will see the exceptions on the console:

c.e.m.a.GetTransactionIsolationAspect    : The exception captured:
java.sql.SQLException: Could not map transaction isolation '<empty>' to a valid JDBC level.
	at com.mysql.cj.jdbc.exceptions.SQLError.createSQLException(SQLError.java:130) ~[mysql-connector-j-8.2.0.jar:8.2.0]
	at com.mysql.cj.jdbc.exceptions.SQLError.createSQLException(SQLError.java:98) ~[mysql-connector-j-8.2.0.jar:8.2.0]
	at com.mysql.cj.jdbc.exceptions.SQLError.createSQLException(SQLError.java:90) ~[mysql-connector-j-8.2.0.jar:8.2.0]
	at com.mysql.cj.jdbc.exceptions.SQLError.createSQLException(SQLError.java:64) ~[mysql-connector-j-8.2.0.jar:8.2.0]
	at com.mysql.cj.jdbc.ConnectionImpl.getTransactionIsolation_aroundBody0(ConnectionImpl.java:1183) ~[mysql-connector-j-8.2.0.jar:8.2.0]
	at com.mysql.cj.jdbc.ConnectionImpl$AjcClosure1.run(ConnectionImpl.java:1) ~[mysql-connector-j-8.2.0.jar:8.2.0]
	at org.aspectj.runtime.reflect.JoinPointImpl.proceed(JoinPointImpl.java:179) ~[aspectjweaver-1.9.20.1.jar:?]
	at com.example.manticore.aspect.GetTransactionIsolationAspect.aroundAdvice(GetTransactionIsolationAspect.java:25) ~[classes/:?]
	at com.mysql.cj.jdbc.ConnectionImpl.getTransactionIsolation(ConnectionImpl.java:1171) ~[mysql-connector-j-8.2.0.jar:8.2.0]
	at com.zaxxer.hikari.pool.PoolBase.checkDefaultIsolation(PoolBase.java:480) ~[HikariCP-5.0.1.jar:?]
    ...

This is because HikariCP want to get the default transaction isolation level from Manticore, but Manticore response with the wrong string value. Ref: 1618.

This has been described in Notes on MySQL connectors

...as the connector can try running certain SQL commands not implemented yet in Manticore.

To work arround with this issue, AspectJ is used to capture the exception and return an arbitrary isolation level for Manticore to work with HikariCP.

It should be noted that Manticore do not aim to provide isolation (it is overly isolated), the isolation level returned has no guidance for Manticore.