“好莱坞原则”说“不要打电话给我们,我们会打电话给你”,这就是依赖注入的意义所在。在你的情况下,不要去拿dataSource
,dataSource
给你。
有很多方法可以做到这一点。请参阅https://github.com/jeffbrown/asdudemo上的项目。
https://github.com/jeffbrown/asdudemo/blob/master/src/main/groovy/ascudemo/helpers/FirstGroovyClass.groovy
// src/main/groovy/ascudemo/FirstGroovyClass.groovy
package ascudemo.helpers
import groovy.sql.Sql
import groovy.util.logging.Slf4j
import org.springframework.beans.factory.InitializingBean
import javax.sql.DataSource
@Slf4j
class FirstGroovyClass implements InitializingBean {
DataSource dataSource
Sql sql
void logSomeInfo() {
// both have been initialized
log.debug "dataSource: ${dataSource}"
log.debug "sql: ${sql}"
}
@Override
void afterPropertiesSet() throws Exception {
sql = new Sql(dataSource)
}
}
https://github.com/jeffbrown/asdudemo/blob/master/src/main/groovy/ascudemo/helpers/SecondGroovyClass.groovy
// src/main/groovy/ascudemo/SecondGroovyClass.groovy
package ascudemo.helpers
import groovy.sql.Sql
import groovy.util.logging.Slf4j
import javax.annotation.PostConstruct
import javax.sql.DataSource
@Slf4j
class SecondGroovyClass {
DataSource dataSource
Sql sql
void logSomeInfo() {
// both have been initialized
log.debug "dataSource: ${dataSource}"
log.debug "sql: ${sql}"
}
@PostConstruct
void initSql() throws Exception {
sql = new Sql(dataSource)
}
}
https://github.com/jeffbrown/asdudemo/blob/master/src/main/groovy/ascudemo/helpers/ThirdGroovyClass.groovy
// src/main/groovy/ascudemo/SecondGroovyClass.groovy
package ascudemo.helpers
import groovy.sql.Sql
import groovy.util.logging.Slf4j
import org.springframework.beans.BeansException
import org.springframework.context.ApplicationContext
import org.springframework.context.ApplicationContextAware
import javax.sql.DataSource
@Slf4j
class ThirdGroovyClass implements ApplicationContextAware {
Sql sql
void logSomeInfo() {
// sql been initialized
log.debug "sql: ${sql}"
}
@Override
void setApplicationContext(ApplicationContext applicationContext) throws BeansException {
DataSource dataSource = applicationContext.getBean('dataSource', DataSource)
sql = new Sql(dataSource)
}
}
https://github.com/jeffbrown/asdudemo/blob/master/grails-app/controllers/ascudemo/DemoController.groovy
// grails-app/controllers/ascudemo/DemoController.groovy
package ascudemo
class DemoController {
SomeService someService
def index() {
someService.logSomeInfo()
render 'Success'
}
}
https://github.com/jeffbrown/asdudemo/blob/master/grails-app/services/ascudemo/SomeService.groovy
// grails-app/services/ascudemo/SomeService.groovy
package ascudemo
import ascudemo.helpers.FirstGroovyClass
import ascudemo.helpers.SecondGroovyClass
import ascudemo.helpers.ThirdGroovyClass
class SomeService {
FirstGroovyClass firstGroovyBean
SecondGroovyClass secondGroovyBean
ThirdGroovyClass thirdGroovyBean
def logSomeInfo() {
firstGroovyBean.logSomeInfo()
secondGroovyBean.logSomeInfo()
thirdGroovyBean.logSomeInfo()
}
}
https://github.com/jeffbrown/asdudemo/blob/master/grails-app/conf/spring/resources.groovy
// grails-app/conf/spring/resources.groovy
import ascudemo.helpers.FirstGroovyClass
import ascudemo.helpers.SecondGroovyClass
import ascudemo.helpers.ThirdGroovyClass
beans = {
// demonstrates one approach
firstGroovyBean(FirstGroovyClass) { bean ->
bean.autowire = 'byName'
}
// demonstrates another approach
secondGroovyBean(SecondGroovyClass) { bean ->
bean.autowire = 'byName'
}
// demonstrates a third approach
thirdGroovyBean ThirdGroovyClass
}
运行应用程序并向http://localhost:8080/demo/发送请求,这将验证所有 3 种方法都有效。
还有其他方法可以做到这一点,但我希望上述方法之一对您有所帮助。
祝你好运!