Resttemplate connection pool configuration

adopt RestTemplateBuilder Generated by RestTemplate

    @Bean(name = "template")
    RestTemplate template(RestTemplateBuilder restTemplateBuilder) {
        return restTemplateBuilder
                // Company s,  Set connection time , Avoid too many threads being blocked and suspended 
                .setConnectTimeout(Duration.ofSeconds(1))
                .setReadTimeout(Duration.ofSeconds(1))
                .additionalMessageConverters(new MyMappingJackson2HttpMessageConverter())
                .requestFactory(() -> {
                    HttpComponentsClientHttpRequestFactory clientHttpRequestFactory = new HttpComponentsClientHttpRequestFactory();
                    //  Connection pool 
                    HttpClientBuilder httpClientBuilder = HttpClientBuilder.create();
                    // Set up HTTP Connection manager 
                    PoolingHttpClientConnectionManager poolingConnectionManager = new PoolingHttpClientConnectionManager();
                    poolingConnectionManager.setMaxTotal(500); //  Maximum number of connections in connection pool 
                    poolingConnectionManager.setDefaultMaxPerRoute(200); //  Concurrency per host 
                    httpClientBuilder.setConnectionManager(poolingConnectionManager);
                    //  Set up connection pool 
                    clientHttpRequestFactory.setHttpClient(httpClientBuilder.build());
                    return clientHttpRequestFactory;
                })
                .build();
    }

restTemplate Connection of by RequestFactory establish
HttpComponentsClientHttpRequestFactory yes RequestFactory Implementation class , Connection pooling , Yes httpClient quote

RestTemplateBuilder Used to generate restTeamplte
configure Method initialized RequestFactory Object passing buildRequestFactory

    public ClientHttpRequestFactory buildRequestFactory() {
        ClientHttpRequestFactory requestFactory = null;
        if (this.requestFactory != null) {
            requestFactory = (ClientHttpRequestFactory)this.requestFactory.get();
        } else if (this.detectRequestFactory) {
            //  Default connection pool factory 
            requestFactory = (new ClientHttpRequestFactorySupplier()).get();
        }

        if (requestFactory != null && this.requestFactoryCustomizer != null) {
            this.requestFactoryCustomizer.accept(requestFactory);
        }

        return requestFactory;
    }