SpringBoot,Springmvc Spring 知识总结

1 非常经典的初始化resttemplate的方法

通过配置加上条件注解实现，实现功能有设置超时参数，修改传递编码，添加拦截器等

@Configuration
@ConditionalOnClass(value = {RestTemplate.class, HttpClient.class})
public class RestTemplateConfiguration {

@Value("${remote.maxTotalConnect:0}")
private int maxTotalConnect; //连接池的最大连接数默认为0
@Value("${remote.maxConnectPerRoute:200}")
private int maxConnectPerRoute; //单个主机的最大连接数
@Value("${remote.connectTimeout:2000}")
private int connectTimeout; //连接超时默认2s
@Value("${remote.readTimeout:30000}")
private int readTimeout; //读取超时默认30s

//创建HTTP客户端工厂
private ClientHttpRequestFactory createFactory() {
if (this.maxTotalConnect <= 0) {
SimpleClientHttpRequestFactory factory = new SimpleClientHttpRequestFactory();
factory.setConnectTimeout(this.connectTimeout);
factory.setReadTimeout(this.readTimeout);
return factory;
}
HttpClient httpClient = HttpClientBuilder.create().setMaxConnTotal(this.maxTotalConnect)
.setMaxConnPerRoute(this.maxConnectPerRoute).build();
HttpComponentsClientHttpRequestFactory factory = new HttpComponentsClientHttpRequestFactory(
httpClient);
factory.setConnectTimeout(this.connectTimeout);
factory.setReadTimeout(this.readTimeout);
return factory;
}

//初始化RestTemplate,并加入spring的Bean工厂，由spring统一管理
@Bean
@ConditionalOnMissingBean(RestTemplate.class)
public RestTemplate getRestTemplate() {
RestTemplate restTemplate = new RestTemplate(this.createFactory());
List<HttpMessageConverter<?>> converterList = restTemplate.getMessageConverters();

//重新设置StringHttpMessageConverter字符集为UTF-8，解决中文乱码问题
HttpMessageConverter<?> converterTarget = null;
for (HttpMessageConverter<?> item : converterList) {
if (StringHttpMessageConverter.class == item.getClass()) {
converterTarget = item;
break;
}
}
if (null != converterTarget) {
converterList.remove(converterTarget);
}
converterList.add(1, new StringHttpMessageConverter(StandardCharsets.UTF_8));

//加入FastJson转换器根据使用情况进行操作，此段注释，默认使用jackson
//converterList.add(new FastJsonHttpMessageConverter4());
return restTemplate;
}

    private void checkAuthHeaderExist(){
       List<ClientHttpRequestInterceptor> interceptors = restTemplate.getInterceptors();
       boolean hasBasicAuth = false;
       for (int i = 0; i < interceptors.size(); i++) {
           if (interceptors.get(i) instanceof BasicAuthorizationInterceptor) {
               hasBasicAuth =true;
           }
       }
       if(!hasBasicAuth){
           restTemplate.getInterceptors().add(new BasicAuthorizationInterceptor(username,password));
       }

}

2 Spring 异步编程

主要用到了两个注解 @EnableAsync用在配置上 @Async(用在 servicer主类方法里)

步骤有3步骤

@Configure //等价于 spring.xml里面的配置

@EnableAsnyn

@ComponentScna（‘com.abc’）//等价于spring.xml里面的包扫描

Configure类

b @Service

class MyService{

@Async

a(){}

@Async

b(){}

}

3 主测试类

myService.a();b();运行发现ab打印内容循环展示