Question

请告诉我一些我在这里做错的事。首先，我是Gradle和Groovy的新手，出于学习目的，我正和他们一起玩DBUnit。

我尝试了下面列出的代码，我的目标是生成一个从mysql数据库获取数据的数据集。

import groovy.sql.Sql
import org.dbunit.database.DatabaseConnection;
import org.dbunit.database.IDatabaseConnection;
import org.dbunit.dataset.IDataSet;
import org.dbunit.dataset.xml.FlatXmlDataSet;

repositories {
    mavenCentral()
}

configurations {
   dbunit    
}

dependencies {
   dbunit 'dbunit:dbunit:2.2', 
          'junit:junit:4.11', 
          'mysql:mysql-connector-java:5.1.25'
}

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

task listJars << {    
    configurations.dbunit.each { File file -> println file.name }
}

task listTables << {    
    getConnection("mydb").eachRow('show tables') { row -> println row[0] }
}

task generateDataSet << {
    def IDatabaseConnection conn = new DatabaseConnection(getConnection("mydb").connection)
    def IDataSet fullDataSet = conn.createDataSet()
    FlatXmlDataSet.write(fullDataSet, new FileOutputStream("full.xml"))
}


static Sql getConnection(db) {
   def props = [user: 'dbuser', password: 'userpass', allowMultiQueries: 'true'] as Properties
   def url = (db) ? 'jdbc:mysql://host:3306/'.plus(db) : 'jdbc:mysql://host:3306/'
   def driver = 'com.mysql.jdbc.Driver'
   Sql.newInstance(url, props, driver)
}

对我来说奇怪的是所有的MySQL方法都运行良好，我可以得到表的列表，例如连接已经完成，所以mysql-connector-java.jar正在加载（我认为），但是当我添加DBUnit的东西（导入libs和generateDataSet方法）似乎dbunit jar不可用于脚本，我得到以下错误：

FAILURE: Build failed with an exception.

* Where:
Build file '/home/me/tmp/dbunit/build.gradle' line: 5

* What went wrong:
Could not compile build file '/home/me/tmp/dbunit/build.gradle'.
> startup failed:
  build file '/home/me/tmp/dbunit/build.gradle': 5: unable to resolve class      org.dbunit.dataset.xml.FlatXmlDataSet
   @ line 5, column 1.
     import org.dbunit.dataset.xml.FlatXmlDataSet;
     ^

  build file '/home/me/tmp/dbunit/build.gradle': 2: unable to resolve class     org.dbunit.database.DatabaseConnection
   @ line 2, column 1.
     import org.dbunit.database.DatabaseConnection;
     ^

  build file '/home/me/tmp/dbunit/build.gradle': 3: unable to resolve class     org.dbunit.database.IDatabaseConnection
   @ line 3, column 1.
     import org.dbunit.database.IDatabaseConnection;
     ^

   build file '/home/me/tmp/dbunit/build.gradle': 4: unable to resolve class     org.dbunit.dataset.IDataSet
   @ line 4, column 1.
     import org.dbunit.dataset.IDataSet;
     ^

  4 errors

但如果我调用listJars任务，我得到了这个：

:listJars
junit-4.11.jar
mysql-connector-java-5.1.25.jar
hamcrest-core-1.3.jar
xercesImpl-2.6.2.jar
xmlParserAPIs-2.6.2.jar
junit-addons-1.4.jar
poi-2.5.1-final-20040804.jar
commons-collections-3.1.jar
commons-lang-2.1.jar
commons-logging-1.0.4.jar
dbunit-2.2.jar

BUILD SUCCESSFUL

在我的理解中，这意味着所有这些罐子都已加载并可用于脚本，我是对的吗？或者我是否对类加载器的东西做错了什么？

非常感谢。

Answer 1

GroovyObject.class.classLoader.addURL hack不是向构建脚本类路径添加依赖项的正确方法。有时需要让JDBC驱动程序与Groovy一起工作（长篇故事）。以下是如何向构建脚本类路径添加依赖项：

buildscript {
    repositories {
        mavenCentral()
    }

    dependencies {
        classpath "some:library:1.0"
    }
}

// library can be used in the rest of the build script

您可以在Gradle User Guide中了解详情。

Gradle加载mysql-connector jar但没有dbunit jar作为外部依赖，为什么？

1 个答案: