This will act as a transnational bean
First put the below settings to 'Config.groovy'
grails.hibernate.cache.queries = true
grails.databinding.convertEmptyStringsToNull = true
Need to add/modify below contents to 'BuildConfig.groovy' to enable database connection using MYSQL:
grails.project.dependency.resolver = "maven" // or ivy
grails.project.dependency.resolution = {
// inherit Grails' default dependencies
inherits("global") {
// specify dependency exclusions here; for example, uncomment this to disable ehcache:
// excludes 'ehcache'
}
log "error" // log level of Ivy resolver, either 'error', 'warn', 'info', 'debug' or 'verbose'
checksums true // Whether to verify checksums on resolve
legacyResolve false // whether to do a secondary resolve on plugin installation, not advised and here for backwards compatibility
repositories {
inherits true // Whether to inherit repository definitions from plugins
grailsPlugins()
grailsHome()
mavenLocal()
grailsCentral()
mavenCentral()
// uncomment these (or add new ones) to enable remote dependency resolution from public Maven repositories
//mavenRepo "http://repository.codehaus.org"
//mavenRepo "http://download.java.net/maven/2/"
//mavenRepo "http://repository.jboss.com/maven2/"
mavenRepo "https://oauth.googlecode.com/svn/code/maven"
}
dependencies {
// specify dependencies here under either 'build', 'compile', 'runtime', 'test' or 'provided' scopes e.g.
compile "org.springframework:spring-orm:$springVersion"
runtime 'mysql:mysql-connector-java:5.1.29'
runtime 'org.springframework:spring-test:4.0.5.RELEASE'
runtime "commons-httpclient:commons-httpclient:3.1"
runtime "org.apache.httpcomponents:httpclient:4.3.3"
runtime 'net.oauth.core:oauth-httpclient4:20090913'
}
plugins {
build ":tomcat:7.0.55"
runtime ":hibernate4:4.3.6.1"
compile ":rendering:1.0.0"
compile ":browser-detection:0.4.3"
compile ':cache:1.1.8'
compile ":mail:1.0.5"
compile ":asset-pipeline:1.9.9"
compile ':quartz:1.0.2'
}
}
Below may be you database configuration (DataSource.groovy):
dataSource {
pooled = true
jmxExport = true
driverClassName = "com.mysql.jdbc.Driver"
dialect = "org.hibernate.dialect.MySQL5InnoDBDialect"
dbCreate = "update"
username = "root"
password = ""
logSql = false
loggingSql = false
properties {
maxActive = 1000
maxIdle = 100
minIdle = 50
initialSize = 1
minEvictableIdleTimeMillis = 60000
timeBetweenEvictionRunsMillis = 60000
numTestsPerEvictionRun = 3
maxWait = 10000
testOnBorrow = true
testWhileIdle = true
testOnReturn = true
validationQuery = "SELECT 1"
minEvictableIdleTimeMillis = 1800000
timeBetweenEvictionRunsMillis = 1800000
}
}
hibernate {
cache.use_second_level_cache = true
cache.use_query_cache = true
cache.region.factory_class = 'net.sf.ehcache.hibernate.EhCacheRegionFactory'
cache.provider_class = 'net.sf.ehcache.hibernate.EhCacheProvider'
format_sql = false
use_sql_comments = false
}
// environment specific settings
environments {
development {
dataSource {
url = "jdbc:mysql://localhost/db_name?useUnicode=yes&characterEncoding=UTF-8"
logSql = true
loggingSql = true
}
}
test {
dataSource {
url = "jdbc:mysql://localhost/db_name?useUnicode=yes&characterEncoding=UTF-8"
logSql = true
loggingSql = true
}
}
production {
dataSource {
url = "jdbc:mysql://localhost/db_name?useUnicode=yes&characterEncoding=UTF-8"
}
}
}
log4j = {
debug 'org.hibernate.SQL'
trace 'org.hibernate.type.descriptor.sql.BasicBinder'
}
Now create a domain class like below:
package com.pritom
class Home {
Long id
String name
String roll
static constraints = {
name blank: false
roll blank: false, unique: true
}
}
Below is the most important class which will be act as a singleton bean in our system:
package com.pritom
import org.springframework.transaction.annotation.Transactional
/**
* Created by pritom on 21/11/2017.
*/
@Transactional(rollbackFor = [Exception, NoClassDefFoundError])
class MyBean {
{
println("BEAN-INITIALIZATION----------------$from------------------")
}
private String from = null
void setFrom(String x) {
this.from = x
}
void testPrint(String a) {
println("Bean-class=${this.toString()}===${a}-----------$from")
Thread.sleep(2000L)
if (true) new Home(name: "Home-" + Home.count(), roll: String.valueOf(System.currentTimeMillis())).save()
println("Home-count=${Home.count()}")
if (true) throw new NoClassDefFoundError("Yeah!!!")
}
}
We are not completed yet, need to initialize bean from resource.groovy as below:
beans = {
myBean(MyBean) { bean ->
bean.scope = 'singleton' // Set bean as singleton
from = "Resource.groovy" // Set value to a field of class MyBean when initializing
}
}
And finally test bean from some controller like below:
package com.pritom
class HomeController {
def myBean
def index() {
try {
myBean.testPrint("1")
myBean.testPrint("2")
}
catch (Throwable ex) {
println("Error=${ex.getMessage()}")
}
render ""
}
}
And you can download source code from here
