Java项目常见工具类总结
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总结平时项目中使用的工具类🎯🎈🍭
Java项目常见工具类总结
JWT工具类
这里一共涉及四个方法:
- 传入用户信息获得token
- 传入token字符串判断token是否存在与有效
- 传入
HttpServletRequest
,通过获取Header中的token判断是否存在与有效 - 根据token获取用户id
public class JwtUtils
//token过期时间
public static final long EXPIRE = 1000 * 60 * 60 * 24;
//秘钥
public static final String APP_SECRET = "ukc8BDbRigUDaY6pZFfWus2jZWLPHO";
/**
* 获得token
*
* @param id 用户id
* @param nickname 用户昵称
* @return
*/
public static String getJwtToken(String id, String nickname)
String JwtToken = Jwts.builder()
//设置jwt头信息
.setHeaderParam("typ", "JWT")
.setHeaderParam("alg", "HS256")
//设置分类
.setSubject("guli-user")
//设置签发时间
.setIssuedAt(new Date())
//设置过期时间=当前时间+过多久过期的时间
.setExpiration(new Date(System.currentTimeMillis() + EXPIRE))
//设置token主体部分,存储用户信息
.claim("id", id)
.claim("nickname", nickname)
//设置签发算法+秘钥
.signWith(SignatureAlgorithm.HS256, APP_SECRET)
.compact();
return JwtToken;
/**
* 判断token是否存在与有效
*
* @param jwtToken
* @return
*/
public static boolean checkToken(String jwtToken)
if (StringUtils.isEmpty(jwtToken)) return false;
try
//验证token是否是有效的token
Jwts.parser().setSigningKey(APP_SECRET).parseClaimsJws(jwtToken);
catch (Exception e)
e.printStackTrace();
return false;
return true;
/**
* 判断token是否存在与有效
*
* @param request
* @return
*/
public static boolean checkToken(HttpServletRequest request)
try
String jwtToken = request.getHeader("token");
if (StringUtils.isEmpty(jwtToken))
return false;
Jwts.parser().setSigningKey(APP_SECRET).parseClaimsJws(jwtToken);
catch (Exception e)
e.printStackTrace();
return false;
return true;
/**
* 根据token获取会员id
*
* @param request
* @return
*/
public static String getMemberIdByJwtToken(HttpServletRequest request)
String jwtToken = request.getHeader("token");
if (StringUtils.isEmpty(jwtToken)) return "";
Jws<Claims> claimsJws = Jwts.parser().setSigningKey(APP_SECRET).parseClaimsJws(jwtToken);
Claims claims = claimsJws.getBody();
return (String) claims.get("id");
MD5工具类
public final class MD5
/**
* 传入字符串,返回经过MD5加密的后的字符串
*
* @param strSrc 需要加密的字符串
* @return 返回加密后的字符串
*/
public static String encrypt(String strSrc)
try
//用来将字节转换成 16 进制表示的字符
char hexChars[] = '0', '1', '2', '3', '4', '5', '6', '7', '8',
'9', 'a', 'b', 'c', 'd', 'e', 'f';
byte[] bytes = strSrc.getBytes();
//得到实现指定摘要算法的 MessageDigest对象
MessageDigest md = MessageDigest.getInstance("MD5");
//使用指定的 byte数组更新摘要
md.update(bytes);
//通过执行诸如填充之类的最终操作完成哈希计算。在调用此方法之后,摘要被重置
bytes = md.digest();
int j = bytes.length;
char[] chars = new char[j * 2];
int k = 0;
//从第一个字节开始,对每一个字节,转换成 16 进制字符
for (int i = 0; i < bytes.length; i++)
//取第 i 个字节
byte b = bytes[i];
//取字节中高 4 位的数字转换
chars[k++] = hexChars[b >>> 4 & 0xf];
//取字节中低 4 位的数字转换
chars[k++] = hexChars[b & 0xf];
//将转换的结果转换为字符串返回
return new String(chars);
catch (NoSuchAlgorithmException e)
e.printStackTrace();
throw new RuntimeException("MD5加密出错!!+" + e);
public static void main(String[] args)
System.out.println(MD5.encrypt("111111"));
视频点播工具类
得到视频点播需要的初始化对象DefaultAcsClient
:
public class InitVodCilent
/**
* 得到视频点播需要的client
*
* @param accessKeyId id
* @param accessKeySecret 秘钥
* @return 返回DefaultAcsClient对象
* @throws ClientException
*/
public static DefaultAcsClient initVodClient(String accessKeyId, String accessKeySecret) throws ClientException
//点播服务接入区域
String regionId = "cn-shanghai";
DefaultProfile profile = DefaultProfile.getProfile(regionId, accessKeyId, accessKeySecret);
DefaultAcsClient client = new DefaultAcsClient(profile);
return client;
公共常量工具类
对于一些微信支付和阿里云OSS等有许多固定地址的,我们可以使用一个工具类定义为常量,方便获取
这里举个栗子
先在配置文件定义:
# 微信开放平台 appid
wx.open.app_id=wxed995adadav4c01bb89b47
# 微信开放平台 appsecret
wx.open.app_secret=a748251723ad5173ddbsfa4083788de60b90e
# 微信开放平台 重定向url
wx.open.redirect_url=http://localhost:8160/api/ucenter/wx/callback
配置类:
@Component
public class ConstantWxUtils implements InitializingBean
@Value("$wx.open.app_id")
private String appId;
@Value("$wx.open.app_secret")
private String appSecret;
@Value("$wx.open.redirect_url")
private String redirectUrl;
//微信开放平台 appid
public static String WX_OPEN_APP_ID;
//微信开放平台 appsecret
public static String WX_OPEN_APP_SECRET;
//微信开放平台 重定向url
public static String WX_OPEN_REDIRECT_URL;
//保证了这些值已经从配置文件读取了,在进行操作
@Override
public void afterPropertiesSet() throws Exception
WX_OPEN_APP_ID = appId;
WX_OPEN_APP_SECRET = appSecret;
WX_OPEN_REDIRECT_URL = redirectUrl;
日期操作工具类
这里一共涉及二个方法:
- 格式化Date日期,转换为字符串返回
- 在日期date上增加amount天,返回Data
public class DateUtil
private static final String dateFormat = "yyyy-MM-dd";
/**
* 格式化日期
*
* @param date
* @return
*/
public static String formatDate(Date date)
SimpleDateFormat sdf = new SimpleDateFormat(dateFormat);
return sdf.format(date);
/**
* 在日期date上增加amount天
*
* @param date 处理的日期,非null
* @param amount 要加的天数,可能为负数
*/
public static Date addDays(Date date, int amount)
Calendar now = Calendar.getInstance();
now.setTime(date);
now.set(Calendar.DATE, now.get(Calendar.DATE) + amount);
return now.getTime();
public static void main(String[] args)
System.out.println(DateUtil.formatDate(new Date()));
System.out.println(DateUtil.formatDate(DateUtil.addDays(new Date(), -1)));
Http客户端工具类
封装一个HttpClientUtils
,可以实现:
- 发送一个 Post 请求
- 提交form表单
- 发送一个 GET 请求
public class HttpClientUtils
public static final int connTimeout=10000;
public static final int readTimeout=10000;
public static final String charset="UTF-8";
private static HttpClient client = null;
static
PoolingHttpClientConnectionManager cm = new PoolingHttpClientConnectionManager();
cm.setMaxTotal(128);
cm.setDefaultMaxPerRoute(128);
client = HttpClients.custom().setConnectionManager(cm).build();
public static String postParameters(String url, String parameterStr) throws ConnectTimeoutException, SocketTimeoutException, Exception
return post(url,parameterStr,"application/x-www-form-urlencoded",charset,connTimeout,readTimeout);
public static String postParameters(String url, String parameterStr,String charset, Integer connTimeout, Integer readTimeout) throws ConnectTimeoutException, SocketTimeoutException, Exception
return post(url,parameterStr,"application/x-www-form-urlencoded",charset,connTimeout,readTimeout);
public static String postParameters(String url, Map<String, String> params) throws ConnectTimeoutException,
SocketTimeoutException, Exception
return postForm(url, params, null, connTimeout, readTimeout);
public static String postParameters(String url, Map<String, String> params, Integer connTimeout,Integer readTimeout) throws ConnectTimeoutException,
SocketTimeoutException, Exception
return postForm(url, params, null, connTimeout, readTimeout);
public static String get(String url) throws Exception
return get(url, charset, null, null);
public static String get(String url, String charset) throws Exception
return get(url, charset, connTimeout, readTimeout);
/**
* 发送一个 Post 请求, 使用指定的字符集编码
*
* @param url 请求地址
* @param body RequestBody
* @param mimeType 例如 application/xml "application/x-www-form-urlencoded" a=1&b=2&c=3
* @param charset 编码
* @param connTimeout 建立链接超时时间,毫秒.
* @param readTimeout 响应超时时间,毫秒.
* @return ResponseBody, 使用指定的字符集编码.
* @throws ConnectTimeoutException 建立链接超时异常
* @throws SocketTimeoutException 响应超时
* @throws Exception
*/
public static String post(String url, String body, String mimeType,String charset, Integer connTimeout, Integer readTimeout)
throws ConnectTimeoutException, SocketTimeoutException, Exception
HttpClient client = null;
//创建Http Post请求
HttpPost post = new HttpPost(url);
String result = "";
try
if (StringUtils.isNotBlank(body))
HttpEntity entity = new StringEntity(body, ContentType.create(mimeType, charset));
post.setEntity(entity);
// 设置参数
Builder customReqConf = RequestConfig.custom();
if (connTimeout != null)
customReqConf.setConnectTimeout(connTimeout);
if (readTimeout != null)
customReqConf.setSocketTimeout(readTimeout);
post.setConfig(customReqConf.build());
HttpResponse res;
if (url.startsWith("https"))
// 执行 Https 请求
client = createSSLInsecureClient();
res = client.execute(post);
else
// 执行 Http 请求
client = HttpClientUtils.client;
res = client.execute(post);
result = IOUtils.toString(res.getEntity().getContent(), charset);
finally
post.releaseConnection();
if (url.startsWith("https") && client != null&& client instanceof CloseableHttpClient)
((CloseableHttpClient) client).close();
return result;
/**
* 提交form表单
*
* @param url
* @param params
* @param connTimeout
* @param readTimeout
* @return
* @throws ConnectTimeoutException
* @throws SocketTimeoutException
* @throws Exception
*/
public static String postForm(String url, Map<String, String> params, Map<String, String> headers, Integer connTimeout,Integer readTimeout) throws ConnectTimeoutException,
SocketTimeoutException, Exception
HttpClient client = null;
HttpPost post = new HttpPost(url);
try
if (params != null && !params.isEmpty())
List<NameValuePair> formParams = new ArrayList<NameValuePair>();
Set<Entry<String, String>> entrySet = params.entrySet();
for (Entry<String, String> entry : entrySet)
formParams.add(new BasicNameValuePair(entry.getKey(), entry.getValue()));
UrlEncodedFormEntity entity = new UrlEncodedFormEntity(formParams, 以上是关于Java项目常见工具类总结的主要内容,如果未能解决你的问题,请参考以下文章