Skip to main content

Spring Framework Annotation- Part 2

By default, <context:component-scan> looks for classes that are annotated with one of a handful of special stereotype annotations:
@Component - A general-purpose stereotype annotation indicating that the class is a Spring component
@Controller - Indicated that the class defines a Spring MVC controller
@Repository - Indicated that the class defines a data repository
@Service - Indicates that the class defines a service
Any custom annotation that is itself annotated with @Component

First, let’s annotate the Guitar class with @Component:
package com.springinaction.springidol;
import org.springframework.stereotype.Component;
public class Guitar implements Instrument{
public void play(){

When Spring scans the com.springinaction.springidol package, it’ll find that
Guitar is annotated with @Component and will automatically register it in Spring. By
default, the bean’s ID will be generated by camel-casing the class name. In the case of
Guitar that means that the bean ID will be guitar.

public classInstrumentalistimplementsPerformer{
// ...
we explicitly named it eddie.


Popular posts from this blog

Stretch a row if data overflows in jasper reports

It is very common that some columns of the report need to stretch to show all the content in that column. But  if you just specify the property " stretch with overflow' to that column(we called text field in jasper report world) , it will just stretch that column and won't change other columns, so the row could be ridiculous. Haven't find the solution from internet yet. So I just review the properties in iReport one by one and find two useful properties(the bold highlighted in example below) which resolve the problems.   example:
<band height="20" splitType="Stretch"> <textField isStretchWithOverflow="true" pattern="" isBlankWhenNull="true"> <reportElement stretchType="RelativeToTallestObject" mode="Opaque" x="192" y="0" width="183" height="20"/> <box leftPadding="2"> <pen lineWidth="0.25"/> …

JasperReports - Configuration Reference

Spring - Operations with jdbcTemplate

This class manages all the database communication and exception handling using a java.sql.Connection that is obtained from the provided DataSource. JdbcTemplate is a stateless and threadsafe class and you can safely instantiate a single instance to be used for each DAO.

Use of Callback Methods
JdbcTemplate is based on a template style of programming common to many other parts of Spring. Some method calls are handled entirely by the JdbcTemplate, while others require the calling class to provide callback methods that contain the implementation for parts of the JDBC workflow. This is another form of Inversion of Control. Your application code hands over the responsibility of managing the database access to the template class. The template class in turn calls back to your application code when it needs some detail processing filled in. These callback methods are allowed to throw a java.sql.SQLException, since the framework will be able to catch this exception and use its built-in excepti…