Appendix A. Common application properties. Exception Handling in Spring MVC. Spring MVC provides several complimentary approaches to exception handling but, when teaching Spring MVC, I often find that my students are confused or not comfortable with them.
Today I’m going to show you thevarious options available. Our goal is to not handle exceptions explicitly in Controller methodswhere possible. They are a cross-cutting concern better handled separately in dedicated code. There are three options: per exception, per controller or globally. A demonstration application that shows the points discussed here can be found Sample Application below for details.
NOTE: The demo applications has been revamped and updated (October 2014) to use Spring Boot 1.1.8 and is (hopefully) easier to use and understand. Using HTTP Status Codes Normally any unhandled exception thrown when processing a web-request causes the server to return anHTTP 500 response. 18. Data access with JDBC. 18.1 Introduction to Spring Framework JDBC The value-add provided by the Spring Framework JDBC abstraction is perhaps best shown by the sequence of actions outlined in the table below.
The table shows what actions Spring will take care of and which actions are the responsibility of you, the application developer. Philipsorst/angular-rest-springsecurity. 28. Security. If Spring Security is on the classpath then web applications will be secure by default with ‘basic’ authentication on all HTTP endpoints.
To add method-level security to a web application you can also add @EnableGlobalMethodSecurity with your desired settings. Additional information can be found in the Spring Security Reference. The default AuthenticationManager has a single user (‘user’ username and random password, printed at INFO level when the application starts up) Using default security password: 78fa095d-3f4c-48b1-ad50-e24c31d5cf35 You can change the password by providing a security.user.password. The default security configuration is implemented in SecurityAutoConfiguration and in the classes imported from there (SpringBootWebSecurityConfiguration for web security and AuthenticationManagerConfiguration for authentication configuration which is also relevant in non-web applications).
The basic features you get out of the box in a web application are: Creating a Custom Login Form. The issue is that Spring Security is protecting access to our custom login page.
In particular the following is happening: We make a request to our web applicationSpring Security sees that we are not authenticatedWe are redirected to /loginThe browser requests /loginSpring Security sees that we are not authenticatedWe are redirected to /login … Spring JdbcTemplate Example. This is a tutorial of Spring JDBC Framework.
When we need to interface with databases the Spring JDBC framework provides solutions to all the low-level details, like open/close a connection, prepare and execute SQL statements, process exceptions and handle transactions. Thus, the only thing a developer must do is just define connection parameters and specify the SQL statement to be executed. Spring JDBC provides several approaches and different classes to form the basis for a JDBC database access.
The most popular approach makes use of JdbcTemplate class. This is the central framework class that manages all the database communication and exception handling. Spring JdbcTemplate Querying examples. Here are few examples to show you how to use JdbcTemplate query() methods to query or extract data from database. 1.
Querying for Single Row Here’s two ways to query or extract a single row record from database, and convert it into a model class. Web App Architecture - the Spring MVC - AngularJs stack. Spring MVC and AngularJs together make for a really productive and appealing frontend development stack for building form-intensive web applications.
In this blog post we will see how a form-intensive web app can be built using these technologies, and compare such approach with other available options. A fully functional and secured sample Spring MVC / AngularJs web app can be found in this github repository. We will go over the following topics: Getting Started · Spring Security and Angular JS. In this section we continue our discussion of how to use Spring Security with Angular in a "single page application".
Here we show how to use Spring Session together with Spring Cloud to combine the features of the systems we built in parts II and IV, and actually end up building 3 single page applications with quite different responsibilities. The aim is to build a Gateway (like in part IV) that is used not only for API resources but also to load the UI from a backend server. We simplify the token-wrangling bits of part II by using the Gateway to pass through the authentication to the backends. Then we extend the system to show how we can make local, granular access decisions in the backends, while still controlling identity and authentication at the Gateway. Getting Started · Enabling Cross Origin Requests for a RESTful Web Service.
In Spring’s approach to building RESTful web services, HTTP requests are handled by a controller.
These components are easily identified by the @Controller annotation, and the GreetingController below handles GET requests for /greeting by returning a new instance of the Greeting class: Getting Started · Creating Asynchronous Methods. Next you need to create a service that queries GitHub to find user information. src/main/java/hello/GitHubLookupService.java The GitHubLookupService class uses Spring’s RestTemplate to invoke a remote REST point (api.github.com/users/), and then convert the answer into a User object.
Spring Boot automatically provides a RestTemplateBuilder that customizes the defaults with any auto-configuration bits (i.e. MessageConverter). Getting Started · Managing Transactions. Src/main/java/hello/Application.java @SpringBootApplication is a convenience annotation that adds all of the following: @Configuration tags the class as a source of bean definitions for the application context. @EnableAutoConfiguration tells Spring Boot to start adding beans based on classpath settings, other beans, and various property settings.
Getting Started · Accessing Relational Data using JDBC with Spring. Spring provides a template class called JdbcTemplate that makes it easy to work with SQL relational databases and JDBC. Most JDBC code is mired in resource acquisition, connection management, exception handling, and general error checking that is wholly unrelated to what the code is meant to achieve.