RestTemplate使用实例

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请求携带cookie

RestTemplate restTemplate= new RestTemplate();
HttpHeaders headers=new HttpHeaders();
List<String> cookies=new ArrayList<>();
cookies.add("JSESSIONID="+String.nullToEmpty(jsessionId));
cookies.add("token="+Strings.nullToEmpty(token));
headers.put(HttpHeaders.COOKIE,cookies);
HttpEntity request=new HttpEntity(null,headers);
ResponseEntity<String> response=restTemplate.postForEntity(url,request,String.class);

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post表单

RestTemplate restTemplate=new RestTemplate();
HttpHeaders headers=new HttpHeaders();
headers.setContentType(MediaType.APPLICATION_FROM_URLENCODED);
MultiValueMap<String,String> map=new LinkedMultiValueMap<String,String>();
map.add("title",title);
map.add("userid",toUserId);
HttpEntity<MultiValueMap<String,String>> reqest=new HttpEntity<MultiValueMap<String,String>>(map,headers);
ResponseEntity<String> response=restTemplate.postForEntity(url,request,String.class);

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post json

RestTemplate restTemplate=new RestTemplate();
HttpHeaders headers=new HttpHeaders();
headers.setContentType(MediaType.APPLICATION_JSON);
headers.setAccept(Lists.newArrayList(MediaType.APPLICATION_JSON));
HttpEntity<String> entity=new HttpEntity<String>(requestJSON,headers);
ResponseEntity<String> resp=restTemplate.postForEntity(url,entity,String.class);

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url post

String template=baseUrl+"/demo?app={0}&userId={1}";
String url=MessageFormat.format(template,app,userId);
return restTemplate.postForEntity(url,null,String.class);

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请求图片

RestTemplate restTemplate=new RestTemplate();
HttpHeaders headers=new HttpHeaders();
headers.setAccept(Arrays.asList(MediaType.APPLICATION_OCTET_STREAM));
HttpEntity<String> entity=new HttpEntity<String>(headers);
ResponseEntity<byte[]> response=restTemplate.exchange(url,HttpMethod.GET,entity,byte[].class);
byte[] imageBytes=response.getBody();

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当注入RestTemplate对象时（非Springboot框架），可能会出现错误，找不到所注入的RestTemplate对象，在该程序中添加这段代码即可

@Bean
public RestTemplate restTemplate(){
    return new RestTemplate();
}