java实现 get、put、post、delete请求

1、get

public static String doGet(String strUrl ){
    	String strReturn=""; 
    	HttpGet httpGet = new HttpGet(strUrl);
    	CloseableHttpClient httpclient = null; 
    	CloseableHttpResponse response1=null;
        try {
        	httpclient = HttpClients.createDefault();
        	response1 = httpclient.execute(httpGet); 
            HttpEntity entity1 = response1.getEntity(); 
            strReturn=EntityUtils.toString(entity1) ;
            EntityUtils.consume(entity1); 
        }catch(Exception e){ 
        	e.printStackTrace();
        }finally {  
				try {
					 if(response1!=null)
					response1.close();
				} catch (IOException e) { 
					e.printStackTrace();
				}
        }
    	return strReturn;
    }

2、put

public static String doPut(String strUrl,String param){ 
    	CloseableHttpClient httpclient = HttpClients.createDefault();
	String strReturn="";  
	PutMethod httpput=new PutMethod(strUrl);   
	try {  
		if(param!=null)
		{
			RequestEntity entity = new StringRequestEntity(param, "application/json", "UTF-8");
			httpput.setRequestEntity(entity);
		}
	        httpClient.executeMethod(httpput);
	        byte[] bytes = httpput.getResponseBody(); 
	        strReturn=  new String(bytes) ; 
		} catch (Exception e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		} 
	     return strReturn;
    }

3、post

public static String doPost(String requestUrl, String payload) {
        CloseableHttpClient httpclient = HttpClients.createDefault();
    	String strReturn="";  
	PostMethod httpost = new PostMethod(requestUrl);    
	try { 
		if(payload!=null)
		{
			RequestEntity entity = new StringRequestEntity(payload, "application/json", "UTF-8");
			httpost.setRequestEntity(entity);
		}
	        httpClient.executeMethod(httpost);
	        byte[] bytes = httpost.getResponseBody(); 
	        strReturn=  new String(bytes) ; 
		} catch (Exception e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}
	     return strReturn;
	    }

4、delete

public static void doDelete(String urlToRead) throws Exception {
	    URL url = new URL(urlToRead);
	    HttpURLConnection httpCon = (HttpURLConnection) url.openConnection();
	    httpCon.setDoOutput(true);
	    httpCon.setRequestProperty(
	        "Content-Type", "application/x-www-form-urlencoded" );
	    httpCon.setRequestMethod("DELETE");
	    httpCon.connect();
	    httpCon.disconnect(); 
        
    }