Hi,
The jar is in the classpath, and I can run the java command that the
sqlline script runs directly, and I get the same error.
The following works in a test java program with the CLASSPATH set:
conn =
DriverManager.getConnection("jdbc:mysql://localhost/ssb?" +
"user=root");
I can create a resultset from a SELECT statement and fetch the results.
But this does not (throws ClassNotFound exception):
Class.forName("com.mysql.cj.jdbc.Driver").newInstance();
neither does
Class.forName("com.mysql.cj.jdbc.Driver").newInstance();
I am confused, because the JDBC connection works as long as I don't use
Class.forName. I don't know how to figure out the name of the class that
is actually being used. I'm sorry if this is silly, but I do not have much
java experience. The MySQL documentation says to use
com.mysql.cj.jdbc.Driver:
https://dev.mysql.com/doc/connector-j/8.0/en/connector-j-usagenotes-connect-drivermanager.html
I suppose this is some kind of MySQL JDBC problem, so this may not be the
right mailing list, but if you have any suggestions before I start looking
elsewhere, I would appreciate it.
On Wed, Oct 6, 2021 at 1:59 PM Julian Hyde <jhyde.apa...@gmail.com> wrote:
> It looks as if com.mysql.cj.jdbc.Driver is not on your class path.
>
> If you are launching via SQLLine, you will need to edit the sqlline shell
> script to add a jar (or jars) to your class path.
>
> Julian
>
>
> > On Oct 6, 2021, at 10:43 AM, Justin Swanhart <greenl...@gmail.com>
> wrote:
> >
> > I am probably making some obvious mistake, but I am having a problem
> > getting a simple MySQL JDBC connection working.
> >
> > I have the latest version of the Connector/J MySQL java client driver. I
> > have a MySQL 8 server running on the local machine, and the following
> model
> > JSON:
> > {
> > version: '1.0',
> > defaultSchema: 'ssb',
> > schemas: [
> > {
> > name: 'ssb',
> > type: 'custom',
> > factory: 'org.apache.calcite.adapter.jdbc.JdbcSchema$Factory',
> > operand: {
> > jdbcDriver: 'com.mysql.cj.jdbc.Driver',
> > jdbcUrl: 'jdbc:mysql://localhost/ssb',
> > jdbcUser: 'root',
> > jdbcPassword: ''
> > }
> > }
> > ]
> > }
> >
> > I have the MySQL driver in my CLASSPATH. I can compile a simple test
> > program which verifies that the class com.mysql.jdbc.Driver exists.
> >
> > While the test program works, sqlline does not:
> > $ ./sqlline -d com.mysql.cj.jdbc.Driver -u jdbc:mysql://root@localhost
> /ssb
> > Building Apache Calcite 1.28.0-SNAPSHOT
> > scan complete in 1ms
> > Could not find driver com.mysql.cj.jdbc.Driver
> >
> > Any suggestions about what I might be doing wrong?
> >
> > Using the !connect command yields a large backtrace (while probably not
> > useful, included for completeness):
> > sqlline version 1.11.0
> > sqlline> !connect jdbc:calcite:model=test.json admin admin
> > WARNING: An illegal reflective access operation has occurred
> > WARNING: Illegal reflective access by com.google.protobuf.UnsafeUtil
> >
> (file:/home/justin/.gradle/caches/modules-2/files-2.1/com.google.protobuf/protobuf-java/3.6.1/d06d46ecfd92ec6d0f3b423b4cd81cb38d8b924/protobuf-java-3.6.1.jar)
> > to field java.nio.Buffer.address
> > WARNING: Please consider reporting this to the maintainers of
> > com.google.protobuf.UnsafeUtil
> > WARNING: Use --illegal-access=warn to enable warnings of further illegal
> > reflective access operations
> > WARNING: All illegal access operations will be denied in a future release
> > java.lang.RuntimeException: Error instantiating
> JsonCustomSchema(name=ssb)
> > at org.apache.calcite.model.ModelHandler.visit(ModelHandler.java:277)
> > at
> >
> org.apache.calcite.model.JsonCustomSchema.accept(JsonCustomSchema.java:66)
> > at org.apache.calcite.model.ModelHandler.visit(ModelHandler.java:200)
> > at org.apache.calcite.model.ModelHandler.<init>(ModelHandler.java:106)
> > at org.apache.calcite.jdbc.Driver$1.onConnectionInit(Driver.java:101)
> > at
> >
> org.apache.calcite.avatica.UnregisteredDriver.connect(UnregisteredDriver.java:139)
> > at sqlline.DatabaseConnection.connect(DatabaseConnection.java:135)
> > at sqlline.DatabaseConnection.getConnection(DatabaseConnection.java:192)
> > at sqlline.Commands.connect(Commands.java:1481)
> > at sqlline.Commands.connect(Commands.java:1355)
> > at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native
> > Method)
> > at
> >
> java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
> > at
> >
> java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
> > at java.base/java.lang.reflect.Method.invoke(Method.java:566)
> > at
> >
> sqlline.ReflectiveCommandHandler.execute(ReflectiveCommandHandler.java:44)
> > at sqlline.SqlLine.dispatch(SqlLine.java:818)
> > at sqlline.SqlLine.begin(SqlLine.java:596)
> > at sqlline.SqlLine.start(SqlLine.java:269)
> > at sqlline.SqlLine.main(SqlLine.java:208)
> > Caused by: com.google.common.util.concurrent.UncheckedExecutionException:
> > java.lang.RuntimeException: java.sql.SQLException: Cannot load JDBC
> driver
> > class 'com.mysql.cj.jdbc.Driver'
> > at com.google.common.cache.LocalCache$Segment.get(LocalCache.java:2051)
> > at com.google.common.cache.LocalCache.get(LocalCache.java:3951)
> > at com.google.common.cache.LocalCache.getOrLoad(LocalCache.java:3974)
> > at
> >
> com.google.common.cache.LocalCache$LocalLoadingCache.get(LocalCache.java:4958)
> > at
> >
> com.google.common.cache.LocalCache$LocalLoadingCache.getUnchecked(LocalCache.java:4964)
> > at
> >
> org.apache.calcite.adapter.jdbc.JdbcUtils$DialectPool.get(JdbcUtils.java:116)
> > at
> >
> org.apache.calcite.adapter.jdbc.JdbcSchema.createDialect(JdbcSchema.java:200)
> > at org.apache.calcite.adapter.jdbc.JdbcSchema.create(JdbcSchema.java:136)
> > at org.apache.calcite.adapter.jdbc.JdbcSchema.create(JdbcSchema.java:123)
> > at org.apache.calcite.adapter.jdbc.JdbcSchema.create(JdbcSchema.java:175)
> > at
> >
> org.apache.calcite.adapter.jdbc.JdbcSchema$Factory.create(JdbcSchema.java:570)
> > at org.apache.calcite.model.ModelHandler.visit(ModelHandler.java:272)
> > ... 18 more
> > Caused by: java.lang.RuntimeException: java.sql.SQLException: Cannot load
> > JDBC driver class 'com.mysql.cj.jdbc.Driver'
> > at
> >
> org.apache.calcite.adapter.jdbc.JdbcUtils$DialectPool.dialect(JdbcUtils.java:101)
> > at
> >
> com.google.common.cache.CacheLoader$FunctionToCacheLoader.load(CacheLoader.java:165)
> > at
> >
> com.google.common.cache.LocalCache$LoadingValueReference.loadFuture(LocalCache.java:3529)
> > at
> com.google.common.cache.LocalCache$Segment.loadSync(LocalCache.java:2278)
> > at
> >
> com.google.common.cache.LocalCache$Segment.lockedGetOrLoad(LocalCache.java:2155)
> > at com.google.common.cache.LocalCache$Segment.get(LocalCache.java:2045)
> > ... 29 more
> > Caused by: java.sql.SQLException: Cannot load JDBC driver class
> > 'com.mysql.cj.jdbc.Driver'
> > at
> >
> org.apache.commons.dbcp2.BasicDataSource.createConnectionFactory(BasicDataSource.java:489)
> > at
> >
> org.apache.commons.dbcp2.BasicDataSource.createDataSource(BasicDataSource.java:599)
> > at
> >
> org.apache.commons.dbcp2.BasicDataSource.getConnection(BasicDataSource.java:809)
> > at
> >
> org.apache.calcite.adapter.jdbc.JdbcUtils$DialectPool.dialect(JdbcUtils.java:94)
> > ... 34 more
> > Caused by: java.lang.ClassNotFoundException: com.mysql.cj.jdbc.Driver
> > at
> >
> java.base/jdk.internal.loader.BuiltinClassLoader.loadClass(BuiltinClassLoader.java:581)
> > at
> >
> java.base/jdk.internal.loader.ClassLoaders$AppClassLoader.loadClass(ClassLoaders.java:178)
> > at java.base/java.lang.ClassLoader.loadClass(ClassLoader.java:522)
> > at
> >
> org.apache.commons.dbcp2.BasicDataSource.createConnectionFactory(BasicDataSource.java:483)
> > ... 37 more
>
>
