Groovy program to connect mongo db - mongodb

Question

I am trying to connect mongodb using Groovy language but i am getting error like this (which is posted below) and i have added necessary jar file.I am using mongodb verion : mongodb-driver-3.2.2.jar .
Please help me to solve this problem
Exception in thread "main" java.lang.NoClassDefFoundError: com/mongodb/operation/OperationExecutor
at java.lang.Class.getDeclaredConstructors0(Native Method)
at java.lang.Class.privateGetDeclaredConstructors(Unknown Source)
at java.lang.Class.getDeclaredConstructors(Unknown Source)
at org.codehaus.groovy.reflection.CachedClass$2$1.run(CachedClass.java:69)
at java.security.AccessController.doPrivileged(Native Method)
at org.codehaus.groovy.reflection.CachedClass$2.initValue(CachedClass.java:67)
at org.codehaus.groovy.reflection.CachedClass$2.initValue(CachedClass.java:64)
at org.codehaus.groovy.util.LazyReference.getLocked(LazyReference.java:46)
at org.codehaus.groovy.util.LazyReference.get(LazyReference.java:33)
at org.codehaus.groovy.reflection.CachedClass.getConstructors(CachedClass.java:258)
at groovy.lang.MetaClassImpl.<init>(MetaClassImpl.java:213)
at groovy.lang.MetaClassImpl.<init>(MetaClassImpl.java:223)
at groovy.lang.MetaClassRegistry$MetaClassCreationHandle.createNormalMetaClass(MetaClassRegistry.java:168)
at groovy.lang.MetaClassRegistry$MetaClassCreationHandle.createWithCustomLookup(MetaClassRegistry.java:158)
at groovy.lang.MetaClassRegistry$MetaClassCreationHandle.create(MetaClassRegistry.java:141)
at org.codehaus.groovy.reflection.ClassInfo.getMetaClassUnderLock(ClassInfo.java:209)
at org.codehaus.groovy.reflection.ClassInfo.getMetaClass(ClassInfo.java:241)
at org.codehaus.groovy.runtime.metaclass.MetaClassRegistryImpl.getMetaClass(MetaClassRegistryImpl.java:255)
at org.codehaus.groovy.runtime.InvokerHelper.getMetaClass(InvokerHelper.java:859)
at org.codehaus.groovy.runtime.callsite.CallSiteArray.createCallConstructorSite(CallSiteArray.java:84)
at org.codehaus.groovy.runtime.callsite.CallSiteArray.defaultCallConstructor(CallSiteArray.java:57)
at org.codehaus.groovy.runtime.callsite.AbstractCallSite.callConstructor(AbstractCallSite.java:182)
at org.codehaus.groovy.runtime.callsite.AbstractCallSite.callConstructor(AbstractCallSite.java:194)
at com.sample.MongoService.client(MongoService.groovy:14)
at com.sample.MongoService.collection(MongoService.groovy:21)
at com.sample.MongoService$collection.call(Unknown Source)
at org.codehaus.groovy.runtime.callsite.CallSiteArray.defaultCall(CallSiteArray.java:45)
at org.codehaus.groovy.runtime.callsite.AbstractCallSite.call(AbstractCallSite.java:108)
at org.codehaus.groovy.runtime.callsite.AbstractCallSite.call(AbstractCallSite.java:116)
at com.sample.MongoDBController.method(MongoDBController.groovy:10)
at com.sample.MongoDBController$method.call(Unknown Source)
at org.codehaus.groovy.runtime.callsite.CallSiteArray.defaultCall(CallSiteArray.java:45)
at org.codehaus.groovy.runtime.callsite.AbstractCallSite.call(AbstractCallSite.java:108)
at org.codehaus.groovy.runtime.callsite.AbstractCallSite.call(AbstractCallSite.java:112)
at com.sample.GroovyDemoApp.main(GroovyDemoApp.groovy:12)
Caused by: java.lang.ClassNotFoundException: com.mongodb.operation.OperationExecutor
at java.net.URLClassLoader$1.run(Unknown Source)
at java.security.AccessController.doPrivileged(Native Method)
at java.net.URLClassLoader.findClass(Unknown Source)
at java.lang.ClassLoader.loadClass(Unknown Source)
at sun.misc.Launcher$AppClassLoader.loadClass(Unknown Source)
at java.lang.ClassLoader.loadClass(Unknown Source)
at java.lang.ClassLoader.loadClassInternal(Unknown Source)
... 35 more
Update :
This is my Groovy code. with this code i am trying to connect Mongodb
// error is in this line . i .e -
// The type com.mongodb.operation.CreateIndexesOperation cannot be resolved.
// It is indirectly referenced from required .class files )
package com.sample
import com.mongodb.*
class MongoService {
private static MongoClient mongoClient
private static host = "localhost" //your host name
private static port = 27017 //your port no.
private static databaseName = "db"
public static MongoClient client() {
if(mongoClient == null){
return new MongoClient(host,port)
}else {
return mongoClient
}
}
public DBCollection collection(collectionName) {
DB db = client().getDB(databaseName)
return db.getCollection(collectionName)
}
}

Answer 1

To use the MongoDB driver you can either use the JAR, or #Grab it from Maven.
Using the JAR
To use the JAR, you need to add it to Groovy's classpath. This is done with the -cp argument:
#!/usr/bin/env groovy -cp /path/to/jar/file
println 'Hello'
Using Maven
You can simply use Groovy's #Grab to take care of the dependency for you:
#Grab('org.mongodb:mongodb-driver:3.2.2')
println 'Hello'
Working example
Here's a working example based on the code you posted:
#Grab('org.mongodb:mongodb-driver:3.2.2')
import com.mongodb.MongoClient
import com.mongodb.DBCollection
import com.mongodb.DB
import com.mongodb.BasicDBObject
class MongoService {
private MongoClient mongoClient
def host = "localhost" //your host name
def port = 27017 //your port no.
def databaseName = 'test'
public MongoClient client() {
mongoClient = mongoClient ?: new MongoClient(host, port)
return mongoClient
}
public DBCollection collection(collectionName) {
DB db = client().getDB(databaseName)
return db.getCollection(collectionName)
}
}
def service = new MongoService(databaseName: 'db')
def foo = service.collection('foo')
def data = [
[firstName: 'Jane', lastName: 'Doe'],
[firstName: 'Elvis', lastName: 'Presley']
].collect { it as BasicDBObject }
foo.insert(data)
foo.find().toArray().each {
println it
}
I've never used MongoDB before, so whether my use case is useful or not is debatable.