SqLite & Gradle

问题:

I've added SQLite in build.gradle:

dependencies {
        compile 'org.xerial:sqlite-jdbc:3.8.9.1'
    }

buildscript {
    repositories {
        jcenter()
        mavenCentral()      
    }
    dependencies {
        classpath 'org.xerial:sqlite-jdbc:3.8.9.1'
    }
}

Once I want to connect to SQLite DB in code:

 groovy.sql.Sql.newInstance(dbLocation, "org.sqlite.JDBC")

It complains that :

java.lang.ClassNotFoundException: org.sqlite.JDBC

What is the reason? How can I fix it?

回答1:

The problem is that you need to get the JDBC drivers into the root classloader rather than just being on the generalised classpath.

You have a few options. One of them is to use your own configuration, and then manipulate the root classloader via GroovyObject:

import groovy.sql.Sql

configurations {
    sqllite
}

repositories {
    mavenCentral()
}

dependencies {
    sqllite 'org.xerial:sqlite-jdbc:3.8.9.1'
}

URLClassLoader loader = GroovyObject.class.classLoader
configurations.sqllite.each { File file ->
    loader.addURL(file.toURL())
}

Sql sql = Sql.newInstance('jdbc:sqlite:test.db', "org.sqlite.JDBC")

task checkSql << {
    sql.execute 'CREATE TABLE TIM(name CHAR(50))'
    sql.eachRow('SELECT * FROM sqlite_master') { row ->
        logger.lifecycle row.toString()
    }
}

Then running gradle checkSql should result in:

$ gradle checkSql
:checkSql
[type:table, name:TIM, tbl_name:TIM, rootpage:2, sql:CREATE TABLE TIM(name CHAR(50))]

BUILD SUCCESSFUL

Total time: 4.374 secs

At least, it does in Gradle 2.9