spring boot使用restTemplate調接口（一）

 

 

package org.suifeng.baseframework.api.rest;

import org.apache.http.client.HttpClient;
import org.apache.http.impl.client.HttpClientBuilder;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.autoconfigure.condition.ConditionalOnClass;
import org.springframework.boot.autoconfigure.condition.ConditionalOnMissingBean;
import org.springframework.boot.autoconfigure.condition.ConditionalOnProperty;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.http.client.ClientHttpRequestFactory;
import org.springframework.http.client.HttpComponentsClientHttpRequestFactory;
import org.springframework.http.client.SimpleClientHttpRequestFactory;
import org.springframework.http.converter.HttpMessageConverter;
import org.springframework.http.converter.StringHttpMessageConverter;
import org.springframework.web.client.RestOperations;
import org.springframework.web.client.RestTemplate;
import java.nio.charset.StandardCharsets;
import java.util.Iterator;
import java.util.List;

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

    @Autowired
    private HttpRequestProperties httpRequestProperties;

    @Autowired
    private RestResponseErrorHandler restResponseErrorHandler;

    /**
     * 實例化RestTemplate對象
     */
    @Bean
    public RestTemplate restTemplate(){
        RestTemplate restTemplate = getRestTemplate();
        // 添加自定義請求頭攔截器
//        restTemplate.setInterceptors(Collections.singletonList(headerRequestInterceptor));
        // 捕捉自定義的restException
        restTemplate.setErrorHandler(restResponseErrorHandler);
        return restTemplate;
    }

    /**
     * 創建HTTP客戶端工廠
     */
    private ClientHttpRequestFactory createFactory() {
        if (httpRequestProperties.getMaxTotalConnect() <= 0) {
            SimpleClientHttpRequestFactory factory = new SimpleClientHttpRequestFactory();
            factory.setConnectTimeout(httpRequestProperties.getConnectTimeout());
            factory.setReadTimeout(httpRequestProperties.getReadTimeout());
            return factory;
        }
        HttpClient httpClient = HttpClientBuilder.create().setMaxConnTotal(httpRequestProperties.getMaxTotalConnect())
                .setMaxConnPerRoute(httpRequestProperties.getMaxConnectPerRoute()).build();
        HttpComponentsClientHttpRequestFactory factory = new HttpComponentsClientHttpRequestFactory(httpClient);
        factory.setConnectTimeout(httpRequestProperties.getConnectTimeout());
        factory.setReadTimeout(httpRequestProperties.getReadTimeout());
        return factory;
    }


    /**
     * 重新初始化MessageConverter
     * RestTemplate會默認添加HttpMessageConverter，
     * 而添加的StringHttpMessageConverter默認使用的字符集是ISO-8859-1，
     * 在遇到中文的時候會有亂碼，所以需要移除原有的StringHttpMessageConverter，修改字符集爲UTF-8後重新設置。
     */
    private void reInitMessageConverter(RestTemplate restTemplate) {
        List<HttpMessageConverter<?>> messageConverters = restTemplate.getMessageConverters();
        Iterator<HttpMessageConverter<?>> iterator = messageConverters.iterator();
        while (iterator.hasNext()) {
            HttpMessageConverter<?> converter = iterator.next();
            if (converter instanceof StringHttpMessageConverter) {
                ((StringHttpMessageConverter) converter).setDefaultCharset(StandardCharsets.UTF_8);
            }
        }
    }


    /**
     * 初始化RestTemplate,並加入spring的Bean工廠，由spring統一管理
     */
    @Bean
    @ConditionalOnMissingBean({RestOperations.class, RestTemplate.class})
    public RestTemplate getRestTemplate() {
        RestTemplate restTemplate = new RestTemplate(this.createFactory());
        reInitMessageConverter(restTemplate);
        return restTemplate;
    }

}

package org.suifeng.baseframework.api.rest;

import lombok.Getter;
import lombok.Setter;
import org.springframework.stereotype.Component;

@Setter
@Getter
@Component
public class HttpRequestProperties {

    /**
     * 連接池的最大連接數默認爲0
     */
    private int maxTotalConnect;

    /**
     * 單個主機的最大連接數
     */
    private int maxConnectPerRoute;

    /**
     * 連接超時默認2s
     */
    private int connectTimeout;

    /**
     * 讀取超時默認30s
     */
    private int readTimeout;

}

package org.suifeng.baseframework.api.rest;

import org.suifeng.baseframework.api.common.exception.RestException;
import lombok.extern.slf4j.Slf4j;
import org.apache.commons.io.IOUtils;
import org.springframework.http.HttpStatus;
import org.springframework.http.client.ClientHttpResponse;
import org.springframework.stereotype.Component;
import org.springframework.web.client.DefaultResponseErrorHandler;
import java.io.IOException;

@Slf4j
@Component
public class RestResponseErrorHandler extends DefaultResponseErrorHandler {

	/**
	 * 重寫handleError，拋出RestException
	 */
	@Override
	public void handleError(ClientHttpResponse response) throws IOException {
		HttpStatus statusCode = HttpStatus.resolve(response.getRawStatusCode());
		log.debug("rest call has error: {}", statusCode.toString());
                // 獲取服務端返回的異常信息，並拋出接口異常
                // 此處代碼僅供參考
		String body = IOUtils.toString(response.getBody(),"UTF-8");
		throw new RestException(statusCode,body);
	}
	
}