Project address: github.com/chywx/sprin…
background
As the company’s business is oriented towards the African market, there are some countries where smartphones are not popular, such as Uganda, which is still dominated by feature phones. In order to support feature phones, we need to create a new WAP website to support feature phones (holy shit!).
Technology selection
Because the functional machine does not support JS, it is not practical to use Vue at the front end. JSP, Freemarker, Thymeleaf and other engines can only be used in the form of templates. However, springboot is used at the back end of the final selection of Velocity template
# Simple project architecture
# springboot consolidation velocity
Version selection
Select Spring-boot-starter-Velocity. Springboot 1.4.7 is not supported by earlier versions of Springboot
Pom.xml adds dependencies
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-velocity</artifactId>
</dependency>
Copy the codeApplication.properties Adds the configuration
server.port=2828
spring.velocity.cache=false
spring.velocity.charset=UTF-8
spring.velocity.check-template-location=true
spring.velocity.content-type=text/html
spring.velocity.enabled=true
spring.velocity.prefix=/templates/
spring.velocity.suffix=.vm
Copy the codeAdd demo tests to the Controller layer
@Controller
@RequestMapping("/velocity") public class TestController {// Demo test @requestMapping ("/demo")
public String demo1(Map map) {
map.put("message"."This is the test...");
map.put("time", System.currentTimeMillis());
return "index"; }}Copy the codeTemplates folder, new home index.vm
<html> <body> $! {message} $! {time} </body> </html>Copy the codeVisit the Index page
The simplest springboot http://localhost:2828/velocity/demo ok, finished consolidation velocity
Date and time processing
How do I customize the timestamp format
1. Add the toolbox. XML
The following
<? xml version="1.0" encoding="UTF-8"? > <toolbox> <tool> <key>DateTool</key> <scope>application</scope> <class>org.apache.velocity.tools.generic.DateTool</class> </tool> </toolbox>Copy the codeOf course, if you need to deal with numbers, you can also introduce a tool
2. Specify the location of toolbox. XML
Application. The properties to add spring. Velocity. The toolbox – config – location = / toolbox. The XML
3. Use it on the VM page
< H1 > Date processing </ H1 > Before processing:$time<br> After processing: $! DateTool.format($! time)Copy the code
Unified abnormal page processing
New VelocityExceptionHander
@ControllerAdvice
public class VelocityExceptionHander {
@ExceptionHandler(value = Exception.class)
@ResponseStatus(HttpStatus.INTERNAL_SERVER_ERROR)
public String exceptionHandler(Exception e, HttpServletRequest request) {
System.out.println("Unknown exception! The reason is:" + e);
request.setAttribute("msg", e);
return "500"; }}Copy the codeCreate a 500. VM template page
<html> <body> error <br> $! msg </body> </html>Copy the codeIf an exception occurs later, page 500 is redirected.
Finally, summarize the common basic syntax tags
// RequestMapping("/allDemo")
public String demo3(Map map) {
map.put("amount", 100);
map.put("msg"."dahai");
map.put("sex"."man");
putString(map);
putSportList(map);
map.put("time", System.currentTimeMillis());
return "allDemo";
}
private void putSportList(Map map) {
List<Sport> sportList = new ArrayList<Sport>() {{
add(new Sport(1, "Football"));
add(new Sport(2, "Basketball"));
add(new Sport(3, "tennis"));
add(new Sport(4, "rugby"));
add(new Sport(5, "cricket"));
}};
map.put("sportList", sportList);
Map<Integer, Sport> sportMap = sportList.stream().collect(Collectors.toMap(Sport::getId, s -> s));
map.put("sportMap", sportMap);
}
private void putString(Map map) {
List<String> strings = new ArrayList<>();
strings.add("a");
strings.add("b");
strings.add("c");
map.put("strings", strings);
}
Copy the codeVm Template page
<! DOCTYPE HTML PUBLIC"- / / / / W3C DTD HTML 4.01 Transitional / / EN"
"http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<title>velocity test</title>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8"/> </head> <body> <h1> String type </h1> $! msg <h1>ifTag < / h1 >#if($! sex == 'man')
男
#else
女
#end
<h1>setAction (define variables)</h1>#set($hw = 'ok')
$hw< h1 > generalforCycle < / h1 >#foreach($! s in $! strings)
$s
#end< h1 > objectforCycle < / h1 >#foreach($! sport in $! sportList)$! sport.name #end
<h1>map forCycle < / h1 >#foreach($! sp in $! sportMap.keySet())
$sp $! sportMap.get($sp).name <br>#end< H1 > Date processing </ H1 > Before processing:$time<br> After processing: $! DateTool.format($! Time) <h1> Calculate addition, subtraction, multiplication, and division </h1>#set($jia = $amount + 10)+ 10 =$jia <br>
#set($jian = $amount - 10)- 10 =$jian <br>
#set($cheng = $amount * 10)X = 10$cheng <br>
#set($chu = $amount / 10)Present 10 =$chu <br>
</body>
</html>
Copy the code