[Java Spring] How to use @autowired

https://sites.google.com/site/stevenattw/java/spring-framework/ioc---annotation-autowired

[Software Development] Terminology: Boilerplate

http://en.wikipedia.org/wiki/Boilerplate_%28text%29

http://en.wikipedia.org/wiki/Boilerplate_code


Differences between boilerplate and template?

From : http://www.webopedia.com/TERM/B/boilerplate.html

Template: describes the layout & style information
Boilerplate: actual text & graphics

http://whatis.techtarget.com/definition/boilerplate

boilerplate : actual text / code
template: fill-in-the-blanks boilerplate

[MongoDB] When name goes wrong

db.collectionName.find()

> work

db.collectionName.renameCollection("1")

> operation ok

db.1.find()

> error, illegal collection name




How to rollback?

db.getCollection("1").find()

> work

db.getCollection("1").renameCollection("properCollectionName")

> done



http://blog.onetechnical.com/2013/05/22/how-to-drop-a-mongodb-collection-with-an-illegal-name/

[Java Groovy] Convert Array or Object to String

def numbers = [0, 1, 2, 3, 4, 5] as Integer[]
assert '0 x 1 x 2 x 3 x 4 x 5' == numbers.join(' x ')

def objects = [new URL('http://www.mrhaki.com'), 'mrhaki', new Expando(name: 'mrhaki'), new Date(109, 10, 10)]
assert 'http://www.mrhaki.com,mrhaki,{name=mrhaki},Tue Nov 10 00:00:00 UTC 2009' == objects.join(',')

http://mrhaki.blogspot.hk/2009/10/groovy-goodness-join-elements-to-string.html

[Java] Nested Exception Fundamental

Simple and clear examples below:

http://beginnersbook.com/2013/04/nested-try-catch/

[Spring] [MongoDB] MongoDB Collection Event Listener

Event Listeners:

• onBeforeConvert(E document)
• onAfterConvert(DbObject dbo, E document)
• onBeforeSave(E document)
• onAfterSave( E collection, DbObject dbo)
• ...

How to Use:

Step 1: Write Java class

package com.tsp.event; import javax.annotation.Resource; import org.springframework.data.mongodb.core.mapping.event. AbstractMongoEventListener; // line broken for rendering import com.mongodb.DBObject; /** * @author siva mondi * */ public class UserEventListener extends AbstractMongoEventListener<User> {     @Override     public void onBeforeConvert(User user) {     }     @Override     public void onBeforeSave(User user, DBObject dbo) {     }     @Override     public void onAfterSave(User user, DBObject dbo) {     }     @Override     public void onAfterLoad(DBObject dbo) {     }     @Override     public void onAfterConvert(DBObject dbo, User user) {     } }

Step 2: Register Event Listener in Spring XML

<!-- All The Event Listeners -->    <bean class="com.tsp.event.UserEventListener" />

http://www.27programs.com/2013/10/27/mongodb-collection-event-listeners-spring-data/

http://maciejwalkowiak.pl/blog/2012/05/09/sorting-spring-data-mongodb-collections-using-orderby/

http://docs.spring.io/spring-data/mongodb/docs/current/api/org/springframework/data/mongodb/core/mapping/event/AbstractMongoEventListener.html

[MongoDB] ObjectId to Timestamp Converter

Test data (ObjectId): 54b37110f441a40ce4239497

Return (ISO Timestamp): 2015-01-12T07:00:32.000Z

* Note that _id stores the timestamp to second only, no millisecond value stored :(

http://steveridout.github.io/mongo-object-time/

[JPA] @transient

transient : passing with time; remaining in a place only a brief of time
http://www.thefreedictionary.com/transient

@transient : a field not to be persisted in database
http://stackoverflow.com/questions/2154622/why-does-jpa-have-a-transient-annotation

[Java] HashMap, TreeMap and LinkedHashMap

HashMap - random ordering, after each new insertion
TreeMap - natural ordering by key
LinkedHashMap - ordering by insertion order

http://stackoverflow.com/questions/2889777/difference-between-hashmap-linkedhashmap-and-treemap

[Spring Security] Get Current User

To get the current authentication:

Method 1

      Authentication auth = SecurityContextHolder.getContext().getAuthentication();
      String name = auth.getName(); //get logged in username

 Method 2

User user = (User)SecurityContextHolder.getContext().getAuthentication().getPrincipal();

String name = user.getUsername(); //get logged in username

http://www.mkyong.com/spring-security/get-current-logged-in-username-in-spring-security/

[Spring Security] About CSRF

What is CSRF?

Cross-site request forgery, also known as a one-click attack or session riding and abbreviated as CSRF (sometimes pronounced sea-surf[1]) or XSRF, is a type of malicious exploit of a website whereby unauthorized commands are transmitted from a user that the website trusts.

http://en.wikipedia.org/wiki/Cross-site_request_forgery


Some descriptions are at the bottom of the page:
http://docs.spring.io/autorepo/docs/spring-security/3.2.x/guides/helloworld.html

You can also read (before conclusion):
http://docs.spring.io/autorepo/docs/spring-security/3.2.x/guides/hellomvc.html#security-config-java

For Spring Security, notice that one description says:

" If you were not using Spring MVC taglibs or Thymeleaf, you can access the CsrfToken on the ServletRequest using the attribute _csrf. "

[Spring MVC] Some references for using Spring Security / MVC for web app

Spring Security

http://pro.ctlok.com/2010/02/spring-security-3.html

http://docs.spring.io/autorepo/docs/spring-security/3.2.x/guides/hellomvc.html#security-config-java


Spring Web MVC

http://krams915.blogspot.hk/2010/12/spring-3-mvc-using-modelattribute-in.html

http://www.javacodegeeks.com/2013/04/spring-mvc-hibernate-maven-crud-operations-example.html

http://examples.javacodegeeks.com/enterprise-java/spring/mvc/spring-mvc-form-handling-example/#code


Hindrance of using jsp:

Some of the related .jar files (more precisely .tld files with those jars) have to put into "/WEB-INF/lib", though they are included in the main application's "dist"(or "target") folder.