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Java技术网站 → 『 Java开发技术』 → 『 Java编程技术专题』 → 整理收集的一些常用java工具类

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* 贴子主题: 整理收集的一些常用java工具类

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作者:Jacky 发表时间：2020-12-27 08:56:24

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1.json转换工具

1. package com.taotao.utils;

3. import java.util.List;

5. import com.fasterxml.jackson.core.JsonProcessingException;
6. import com.fasterxml.jackson.databind.JavaType;
7. import com.fasterxml.jackson.databind.JsonNode;
8. import com.fasterxml.jackson.databind.ObjectMapper;

10. /**
11. * json转换工具类
12. */
13. public class JsonUtils {

15. // 定义jackson对象
16. private static final ObjectMapper MAPPER = new ObjectMapper();

18. /**
19. * 将对象转换成json字符串。
20. * Title: pojoToJson
21. * Description: 
22. * @param data
23. * @return
24. */
25. public static String objectToJson(Object data) {
26. try {
27. String string = MAPPER.writeValueAsString(data);
28. return string;
29. } catch (JsonProcessingException e) {
30. e.printStackTrace();
31. }
32. return null;
33. }

35. /**
36. * 将json结果集转化为对象
37. *
38. * @param jsonData json数据
39. * @param clazz 对象中的object类型
40. * @return
41. */
42. public static <T> T jsonToPojo(String jsonData, Class<T> beanType) {
43. try {
44. T t = MAPPER.readValue(jsonData, beanType);
45. return t;
46. } catch (Exception e) {
47. e.printStackTrace();
48. }
49. return null;
50. }

52. /**
53. * 将json数据转换成pojo对象list
54. * Title: jsonToList
55. * Description: 
56. * @param jsonData
57. * @param beanType
58. * @return
59. */
60. public static <T>List<T> jsonToList(String jsonData, Class<T> beanType) {
61. JavaType javaType = MAPPER.getTypeFactory().constructParametricType(List.class, beanType);
62. try {
63. List<T> list = MAPPER.readValue(jsonData, javaType);
64. return list;
65. } catch (Exception e) {
66. e.printStackTrace();
67. }

69. return null;
70. }

72. }

2.cookie的读写

1. package com.taotao.common.utils;

3. import java.io.UnsupportedEncodingException;
4. import java.net.URLDecoder;
5. import java.net.URLEncoder;

7. import javax.servlet.http.Cookie;
8. import javax.servlet.http.HttpServletRequest;
9. import javax.servlet.http.HttpServletResponse;

12. /**
13. *
14. * Cookie 工具类
15. *
16. */
17. public final class CookieUtils {

19. /**
20. * 得到Cookie的值, 不编码
21. *
22. * @param request
23. * @param cookieName
24. * @return
25. */
26. public static String getCookieValue(HttpServletRequest request, String cookieName) {
27. return getCookieValue(request, cookieName, false);
28. }

30. /**
31. * 得到Cookie的值,
32. *
33. * @param request
34. * @param cookieName
35. * @return
36. */
37. public static String getCookieValue(HttpServletRequest request, String cookieName, boolean isDecoder) {
38. Cookie[] cookieList = request.getCookies();
39. if (cookieList == null || cookieName == null) {
40. return null;
41. }
42. String retValue = null;
43. try {
44. for (int i = 0; i < cookieList.length; i++) {
45. if (cookieList[i].getName().equals(cookieName)) {
46. if (isDecoder) {
47. retValue = URLDecoder.decode(cookieList[i].getValue(), "UTF-8");
48. } else {
49. retValue = cookieList[i].getValue();
50. }
51. break;
52. }
53. }
54. } catch (UnsupportedEncodingException e) {
55. e.printStackTrace();
56. }
57. return retValue;
58. }

60. /**
61. * 得到Cookie的值,
62. *
63. * @param request
64. * @param cookieName
65. * @return
66. */
67. public static String getCookieValue(HttpServletRequest request, String cookieName, String encodeString) {
68. Cookie[] cookieList = request.getCookies();
69. if (cookieList == null || cookieName == null) {
70. return null;
71. }
72. String retValue = null;
73. try {
74. for (int i = 0; i < cookieList.length; i++) {
75. if (cookieList[i].getName().equals(cookieName)) {
76. retValue = URLDecoder.decode(cookieList[i].getValue(), encodeString);
77. break;
78. }
79. }
80. } catch (UnsupportedEncodingException e) {
81. e.printStackTrace();
82. }
83. return retValue;
84. }

86. /**
87. * 设置Cookie的值不设置生效时间默认浏览器关闭即失效,也不编码
88. */
89. public static void setCookie(HttpServletRequest request, HttpServletResponse response, String cookieName,
90. String cookieValue) {
91. setCookie(request, response, cookieName, cookieValue, -1);
92. }

94. /**
95. * 设置Cookie的值在指定时间内生效,但不编码
96. */
97. public static void setCookie(HttpServletRequest request, HttpServletResponse response, String cookieName,
98. String cookieValue, int cookieMaxage) {
99. setCookie(request, response, cookieName, cookieValue, cookieMaxage, false);
100. }

102. /**
103. * 设置Cookie的值不设置生效时间,但编码
104. */
105. public static void setCookie(HttpServletRequest request, HttpServletResponse response, String cookieName,
106. String cookieValue, boolean isEncode) {
107. setCookie(request, response, cookieName, cookieValue, -1, isEncode);
108. }

110. /**
111. * 设置Cookie的值在指定时间内生效, 编码参数
112. */
113. public static void setCookie(HttpServletRequest request, HttpServletResponse response, String cookieName,
114. String cookieValue, int cookieMaxage, boolean isEncode) {
115. doSetCookie(request, response, cookieName, cookieValue, cookieMaxage, isEncode);
116. }

118. /**
119. * 设置Cookie的值在指定时间内生效, 编码参数(指定编码)
120. */
121. public static void setCookie(HttpServletRequest request, HttpServletResponse response, String cookieName,
122. String cookieValue, int cookieMaxage, String encodeString) {
123. doSetCookie(request, response, cookieName, cookieValue, cookieMaxage, encodeString);
124. }

126. /**
127. * 删除Cookie带cookie域名
128. */
129. public static void deleteCookie(HttpServletRequest request, HttpServletResponse response,
130. String cookieName) {
131. doSetCookie(request, response, cookieName, "", -1, false);
132. }

134. /**
135. * 设置Cookie的值，并使其在指定时间内生效
136. *
137. * @param cookieMaxage cookie生效的最大秒数
138. */
139. private static final void doSetCookie(HttpServletRequest request, HttpServletResponse response,
140. String cookieName, String cookieValue, int cookieMaxage, boolean isEncode) {
141. try {
142. if (cookieValue == null) {
143. cookieValue = "";
144. } else if (isEncode) {
145. cookieValue = URLEncoder.encode(cookieValue, "utf-8");
146. }
147. Cookie cookie = new Cookie(cookieName, cookieValue);
148. if (cookieMaxage > 0)
149. cookie.setMaxAge(cookieMaxage);
150. if (null != request) {// 设置域名的cookie
151. String domainName = getDomainName(request);
152. System.out.println(domainName);
153. if (!"localhost".equals(domainName)) {
154. cookie.setDomain(domainName);
155. }
156. }
157. cookie.setPath("/");
158. response.addCookie(cookie);
159. } catch (Exception e) {
160. e.printStackTrace();
161. }
162. }

164. /**
165. * 设置Cookie的值，并使其在指定时间内生效
166. *
167. * @param cookieMaxage cookie生效的最大秒数
168. */
169. private static final void doSetCookie(HttpServletRequest request, HttpServletResponse response,
170. String cookieName, String cookieValue, int cookieMaxage, String encodeString) {
171. try {
172. if (cookieValue == null) {
173. cookieValue = "";
174. } else {
175. cookieValue = URLEncoder.encode(cookieValue, encodeString);
176. }
177. Cookie cookie = new Cookie(cookieName, cookieValue);
178. if (cookieMaxage > 0)
179. cookie.setMaxAge(cookieMaxage);
180. if (null != request) {// 设置域名的cookie
181. String domainName = getDomainName(request);
182. System.out.println(domainName);
183. if (!"localhost".equals(domainName)) {
184. cookie.setDomain(domainName);
185. }
186. }
187. cookie.setPath("/");
188. response.addCookie(cookie);
189. } catch (Exception e) {
190. e.printStackTrace();
191. }
192. }

194. /**
195. * 得到cookie的域名
196. */
197. private static final String getDomainName(HttpServletRequest request) {
198. String domainName = null;

200. String serverName = request.getRequestURL().toString();
201. if (serverName == null || serverName.equals("")) {
202. domainName = "";
203. } else {
204. serverName = serverName.toLowerCase();
205. serverName = serverName.substring(7);
206. final int end = serverName.indexOf("/");
207. serverName = serverName.substring(0, end);
208. final String[] domains = serverName.split("\\.");
209. int len = domains.length;
210. if (len > 3) {
211. // www.xxx.com.cn
212. domainName = "." + domains[len - 3] + "." + domains[len - 2] + "." + domains[len - 1];
213. } else if (len <= 3 && len > 1) {
214. // xxx.com or xxx.cn
215. domainName = "." + domains[len - 2] + "." + domains[len - 1];
216. } else {
217. domainName = serverName;
218. }
219. }

221. if (domainName != null && domainName.indexOf(":") > 0) {
222. String[] ary = domainName.split("\\:");
223. domainName = ary[0];
224. }
225. return domainName;
226. }

228. }

3.HttpClientUtil

1. package com.taotao.utils;

3. import java.io.IOException;
4. import java.net.URI;
5. import java.util.ArrayList;
6. import java.util.List;
7. import java.util.Map;

9. import org.apache.http.NameValuePair;
10. import org.apache.http.client.entity.UrlEncodedFormEntity;
11. import org.apache.http.client.methods.CloseableHttpResponse;
12. import org.apache.http.client.methods.HttpGet;
13. import org.apache.http.client.methods.HttpPost;
14. import org.apache.http.client.utils.URIBuilder;
15. import org.apache.http.entity.ContentType;
16. import org.apache.http.entity.StringEntity;
17. import org.apache.http.impl.client.CloseableHttpClient;
18. import org.apache.http.impl.client.HttpClients;
19. import org.apache.http.message.BasicNameValuePair;
20. import org.apache.http.util.EntityUtils;

22. public class HttpClientUtil {

24. public static String doGet(String url, Map<String, String> param) {

26. // 创建Httpclient对象
27. CloseableHttpClient httpclient = HttpClients.createDefault();

29. String resultString = "";
30. CloseableHttpResponse response = null;
31. try {
32. // 创建uri
33. URIBuilder builder = new URIBuilder(url);
34. if (param != null) {
35. for (String key : param.keySet()) {
36. builder.addParameter(key, param.get(key));
37. }
38. }
39. URI uri = builder.build();

41. // 创建http GET请求
42. HttpGet httpGet = new HttpGet(uri);

44. // 执行请求
45. response = httpclient.execute(httpGet);
46. // 判断返回状态是否为200
47. if (response.getStatusLine().getStatusCode() == 200) {
48. resultString = EntityUtils.toString(response.getEntity(), "UTF-8");
49. }
50. } catch (Exception e) {
51. e.printStackTrace();
52. } finally {
53. try {
54. if (response != null) {
55. response.close();
56. }
57. httpclient.close();
58. } catch (IOException e) {
59. e.printStackTrace();
60. }
61. }
62. return resultString;
63. }

65. public static String doGet(String url) {
66. return doGet(url, null);
67. }

69. public static String doPost(String url, Map<String, String> param) {
70. // 创建Httpclient对象
71. CloseableHttpClient httpClient = HttpClients.createDefault();
72. CloseableHttpResponse response = null;
73. String resultString = "";
74. try {
75. // 创建Http Post请求
76. HttpPost httpPost = new HttpPost(url);
77. // 创建参数列表
78. if (param != null) {
79. List<NameValuePair> paramList = new ArrayList<>();
80. for (String key : param.keySet()) {
81. paramList.add(new BasicNameValuePair(key, param.get(key)));
82. }
83. // 模拟表单
84. UrlEncodedFormEntity entity = new UrlEncodedFormEntity(paramList);
85. httpPost.setEntity(entity);
86. }
87. // 执行http请求
88. response = httpClient.execute(httpPost);
89. resultString = EntityUtils.toString(response.getEntity(), "utf-8");
90. } catch (Exception e) {
91. e.printStackTrace();
92. } finally {
93. try {
94. response.close();
95. } catch (IOException e) {
96. // TODO Auto-generated catch block
97. e.printStackTrace();
98. }
99. }

101. return resultString;
102. }

104. public static String doPost(String url) {
105. return doPost(url, null);
106. }

108. public static String doPostJson(String url, String json) {
109. // 创建Httpclient对象
110. CloseableHttpClient httpClient = HttpClients.createDefault();
111. CloseableHttpResponse response = null;
112. String resultString = "";
113. try {
114. // 创建Http Post请求
115. HttpPost httpPost = new HttpPost(url);
116. // 创建请求内容
117. StringEntity entity = new StringEntity(json, ContentType.APPLICATION_JSON);
118. httpPost.setEntity(entity);
119. // 执行http请求
120. response = httpClient.execute(httpPost);
121. resultString = EntityUtils.toString(response.getEntity(), "utf-8");
122. } catch (Exception e) {
123. e.printStackTrace();
124. } finally {
125. try {
126. response.close();
127. } catch (IOException e) {
128. // TODO Auto-generated catch block
129. e.printStackTrace();
130. }
131. }

133. return resultString;
134. }
135. }

4.FastDFSClient工具类

1. package cn.itcast.fastdfs.cliennt;

3. import org.csource.common.NameValuePair;
4. import org.csource.fastdfs.ClientGlobal;
5. import org.csource.fastdfs.StorageClient1;
6. import org.csource.fastdfs.StorageServer;
7. import org.csource.fastdfs.TrackerClient;
8. import org.csource.fastdfs.TrackerServer;

10. public class FastDFSClient {

12. private TrackerClient trackerClient = null;
13. private TrackerServer trackerServer = null;
14. private StorageServer storageServer = null;
15. private StorageClient1 storageClient = null;

17. public FastDFSClient(String conf) throws Exception {
18. if (conf.contains("classpath:")) {
19. conf = conf.replace("classpath:", this.getClass().getResource("/").getPath());
20. }
21. ClientGlobal.init(conf);
22. trackerClient = new TrackerClient();
23. trackerServer = trackerClient.getConnection();
24. storageServer = null;
25. storageClient = new StorageClient1(trackerServer, storageServer);
26. }

28. /**
29. * 上传文件方法
30. * Title: uploadFile
31. * Description: 
32. * @param fileName 文件全路径
33. * @param extName 文件扩展名，不包含（.）
34. * @param metas 文件扩展信息
35. * @return
36. * @throws Exception
37. */
38. public String uploadFile(String fileName, String extName, NameValuePair[] metas) throws Exception {
39. String result = storageClient.upload_file1(fileName, extName, metas);
40. return result;
41. }

43. public String uploadFile(String fileName) throws Exception {
44. return uploadFile(fileName, null, null);
45. }

47. public String uploadFile(String fileName, String extName) throws Exception {
48. return uploadFile(fileName, extName, null);
49. }

51. /**
52. * 上传文件方法
53. * Title: uploadFile
54. * Description: 
55. * @param fileContent 文件的内容，字节数组
56. * @param extName 文件扩展名
57. * @param metas 文件扩展信息
58. * @return
59. * @throws Exception
60. */
61. public String uploadFile(byte[] fileContent, String extName, NameValuePair[] metas) throws Exception {

63. String result = storageClient.upload_file1(fileContent, extName, metas);
64. return result;
65. }

67. public String uploadFile(byte[] fileContent) throws Exception {
68. return uploadFile(fileContent, null, null);
69. }

71. public String uploadFile(byte[] fileContent, String extName) throws Exception {
72. return uploadFile(fileContent, extName, null);
73. }
74. }

1. public class FastDFSTest {

3. @Test
4. public void testFileUpload() throws Exception {
5. // 1、加载配置文件，配置文件中的内容就是tracker服务的地址。
6. ClientGlobal.init("D:/workspaces-itcast/term197/taotao-manager-web/src/main/resources/resource/client.conf");
7. // 2、创建一个TrackerClient对象。直接new一个。
8. TrackerClient trackerClient = new TrackerClient();
9. // 3、使用TrackerClient对象创建连接，获得一个TrackerServer对象。
10. TrackerServer trackerServer = trackerClient.getConnection();
11. // 4、创建一个StorageServer的引用，值为null
12. StorageServer storageServer = null;
13. // 5、创建一个StorageClient对象，需要两个参数TrackerServer对象、StorageServer的引用
14. StorageClient storageClient = new StorageClient(trackerServer, storageServer);
15. // 6、使用StorageClient对象上传图片。
16. //扩展名不带“.”
17. String[] strings = storageClient.upload_file("D:/Documents/Pictures/images/200811281555127886.jpg", "jpg", null);
18. // 7、返回数组。包含组名和图片的路径。
19. for (String string : strings) {
20. System.out.println(string);
21. }
22. }
23. }

# ![image](http://upload-images.jianshu.io/upload_images/2509688-45370c9d24b87e31?imageMogr2/auto-orient/strip%7CimageView2/2/w/1240)

5.获取异常的堆栈信息

1.  package com.taotao.utils;

3.  import java.io.PrintWriter;
4.  import java.io.StringWriter;

6.  public class ExceptionUtil {

8.  /**
9.  * 获取异常的堆栈信息
10.  *
11.  * @param t
12.  * @return
13.  */
14.  public static String getStackTrace(Throwable t) {
15.  StringWriter sw = new StringWriter();
16.  PrintWriter pw = new PrintWriter(sw);

18.  try {
19.  t.printStackTrace(pw);
20.  return sw.toString();
21.  } finally {
22.  pw.close();
23.  }
24.  }
25.  }

#6.easyUIDataGrid对象返回值

1. package com.taotao.result;

3. import java.util.List;

5. /**
6. * easyUIDataGrid对象返回值
7. * Title: EasyUIResult
8. * Description: 
9. * Company: www.itcast.com
10. * @author 入云龙
11. * @date 2015年7月21日下午4:12:52
12. * @version 1.0
13. */
14. public class EasyUIResult {

16. private Integer total;

18. private List<?> rows;

20. public EasyUIResult(Integer total, List<?> rows) {
21. this.total = total;
22. this.rows = rows;
23. }

25. public EasyUIResult(long total, List<?> rows) {
26. this.total = (int) total;
27. this.rows = rows;
28. }

30. public Integer getTotal() {
31. return total;
32. }
33. public void setTotal(Integer total) {
34. this.total = total;
35. }
36. public List<?> getRows() {
37. return rows;
38. }
39. public void setRows(List<?> rows) {
40. this.rows = rows;
41. }

44. }

7.ftp上传下载工具类

1. package com.taotao.utils;

3. import java.io.File;
4. import java.io.FileInputStream;
5. import java.io.FileNotFoundException;
6. import java.io.FileOutputStream;
7. import java.io.IOException;
8. import java.io.InputStream;
9. import java.io.OutputStream;

11. import org.apache.commons.net.ftp.FTP;
12. import org.apache.commons.net.ftp.FTPClient;
13. import org.apache.commons.net.ftp.FTPFile;
14. import org.apache.commons.net.ftp.FTPReply;

16. /**
17. * ftp上传下载工具类
18. * Title: FtpUtil
19. * Description: 
20. * Company: www.itcast.com
21. * @author 入云龙
22. * @date 2015年7月29日下午8:11:51
23. * @version 1.0
24. */
25. public class FtpUtil {

27. /**
28. * Description: 向FTP服务器上传文件
29. * @param host FTP服务器hostname
30. * @param port FTP服务器端口
31. * @param username FTP登录账号
32. * @param password FTP登录密码
33. * @param basePath FTP服务器基础目录
34. * @param filePath FTP服务器文件存放路径。例如分日期存放：/2015/01/01。文件的路径为basePath+filePath
35. * @param filename 上传到FTP服务器上的文件名
36. * @param input 输入流
37. * @return 成功返回true，否则返回false
38. */
39. public static boolean uploadFile(String host, int port, String username, String password, String basePath,
40. String filePath, String filename, InputStream input) {
41. boolean result = false;
42. FTPClient ftp = new FTPClient();
43. try {
44. int reply;
45. ftp.connect(host, port);// 连接FTP服务器
46. // 如果采用默认端口，可以使用ftp.connect(host)的方式直接连接FTP服务器
47. ftp.login(username, password);// 登录
48. reply = ftp.getReplyCode();
49. if (!FTPReply.isPositiveCompletion(reply)) {
50. ftp.disconnect();
51. return result;
52. }
53. //切换到上传目录
54. if (!ftp.changeWorkingDirectory(basePath+filePath)) {
55. //如果目录不存在创建目录
56. String[] dirs = filePath.split("/");
57. String tempPath = basePath;
58. for (String dir : dirs) {
59. if (null == dir || "".equals(dir)) continue;
60. tempPath += "/" + dir;
61. if (!ftp.changeWorkingDirectory(tempPath)) {
62. if (!ftp.makeDirectory(tempPath)) {
63. return result;
64. } else {
65. ftp.changeWorkingDirectory(tempPath);
66. }
67. }
68. }
69. }
70. //设置上传文件的类型为二进制类型
71. ftp.setFileType(FTP.BINARY_FILE_TYPE);
72. //上传文件
73. if (!ftp.storeFile(filename, input)) {
74. return result;
75. }
76. input.close();
77. ftp.logout();
78. result = true;
79. } catch (IOException e) {
80. e.printStackTrace();
81. } finally {
82. if (ftp.isConnected()) {
83. try {
84. ftp.disconnect();
85. } catch (IOException ioe) {
86. }
87. }
88. }
89. return result;
90. }

92. /**
93. * Description: 从FTP服务器下载文件
94. * @param host FTP服务器hostname
95. * @param port FTP服务器端口
96. * @param username FTP登录账号
97. * @param password FTP登录密码
98. * @param remotePath FTP服务器上的相对路径
99. * @param fileName 要下载的文件名
100. * @param localPath 下载后保存到本地的路径
101. * @return
102. */
103. public static boolean downloadFile(String host, int port, String username, String password, String remotePath,
104. String fileName, String localPath) {
105. boolean result = false;
106. FTPClient ftp = new FTPClient();
107. try {
108. int reply;
109. ftp.connect(host, port);
110. // 如果采用默认端口，可以使用ftp.connect(host)的方式直接连接FTP服务器
111. ftp.login(username, password);// 登录
112. reply = ftp.getReplyCode();
113. if (!FTPReply.isPositiveCompletion(reply)) {
114. ftp.disconnect();
115. return result;
116. }
117. ftp.changeWorkingDirectory(remotePath);// 转移到FTP服务器目录
118. FTPFile[] fs = ftp.listFiles();
119. for (FTPFile ff : fs) {
120. if (ff.getName().equals(fileName)) {
121. File localFile = new File(localPath + "/" + ff.getName());

123. OutputStream is = new FileOutputStream(localFile);
124. ftp.retrieveFile(ff.getName(), is);
125. is.close();
126. }
127. }

129. ftp.logout();
130. result = true;
131. } catch (IOException e) {
132. e.printStackTrace();
133. } finally {
134. if (ftp.isConnected()) {
135. try {
136. ftp.disconnect();
137. } catch (IOException ioe) {
138. }
139. }
140. }
141. return result;
142. }

144. public static void main(String[] args) {
145. try {
146. FileInputStream in=new FileInputStream(new File("D:\\temp\\image\\gaigeming.jpg"));
147. boolean flag = uploadFile("192.168.25.133", 21, "ftpuser", "ftpuser", "/home/ftpuser/www/images","/2015/01/21", "gaigeming.jpg", in);
148. System.out.println(flag);
149. } catch (FileNotFoundException e) {
150. e.printStackTrace();
151. }
152. }
153. }

8.各种id生成策略

1. package com.taotao.utils;

3. import java.util.Random;

5. /**
6. * 各种id生成策略
7. * Title: IDUtils
8. * Description: 
9. * @date 2015年7月22日下午2:32:10
10. * @version 1.0
11. */
12. public class IDUtils {

14. /**
15. * 图片名生成
16. */
17. public static String genImageName() {
18. //取当前时间的长整形值包含毫秒
19. long millis = System.currentTimeMillis();
20. //long millis = System.nanoTime();
21. //加上三位随机数
22. Random random = new Random();
23. int end3 = random.nextInt(999);
24. //如果不足三位前面补0
25. String str = millis + String.format("%03d", end3);

27. return str;
28. }

30. /**
31. * 商品id生成
32. */
33. public static long genItemId() {
34. //取当前时间的长整形值包含毫秒
35. long millis = System.currentTimeMillis();
36. //long millis = System.nanoTime();
37. //加上两位随机数
38. Random random = new Random();
39. int end2 = random.nextInt(99);
40. //如果不足两位前面补0
41. String str = millis + String.format("%02d", end2);
42. long id = new Long(str);
43. return id;
44. }

46. public static void main(String[] args) {
47. for(int i=0;i< 100;i++)
48. System.out.println(genItemId());
49. }
50. }

##9.上传图片返回值

1. package com.result;
2. /**
3. * 上传图片返回值
4. * Title: PictureResult
5. * Description: 
6. * Company: www.itcast.com
7. * @author 入云龙
8. * @date 2015年7月22日下午2:09:02
9. * @version 1.0
10. */
11. public class PictureResult {

13. /**
14. * 上传图片返回值，成功：0 失败：1
15. */
16. private Integer error;
17. /**
18. * 回显图片使用的url
19. */
20. private String url;
21. /**
22. * 错误时的错误消息
23. */
24. private String message;
25. public PictureResult(Integer state, String url) {
26. this.url = url;
27. this.error = state;
28. }
29. public PictureResult(Integer state, String url, String errorMessage) {
30. this.url = url;
31. this.error = state;
32. this.message = errorMessage;
33. }
34. public Integer getError() {
35. return error;
36. }
37. public void setError(Integer error) {
38. this.error = error;
39. }
40. public String getUrl() {
41. return url;
42. }
43. public void setUrl(String url) {
44. this.url = url;
45. }
46. public String getMessage() {
47. return message;
48. }
49. public void setMessage(String message) {
50. this.message = message;
51. }

53. }

10.自定义响应结构

1. package com.result;

3. import java.util.List;

5. import com.fasterxml.jackson.databind.JsonNode;
6. import com.fasterxml.jackson.databind.ObjectMapper;

8. /**
9. * 自定义响应结构
10. */
11. public class TaotaoResult {

13. // 定义jackson对象
14. private static final ObjectMapper MAPPER = new ObjectMapper();

16. // 响应业务状态
17. private Integer status;

19. // 响应消息
20. private String msg;

22. // 响应中的数据
23. private Object data;

25. public static TaotaoResult build(Integer status, String msg, Object data) {
26. return new TaotaoResult(status, msg, data);
27. }

29. public static TaotaoResult ok(Object data) {
30. return new TaotaoResult(data);
31. }

33. public static TaotaoResult ok() {
34. return new TaotaoResult(null);
35. }

37. public TaotaoResult() {

39. }

41. public static TaotaoResult build(Integer status, String msg) {
42. return new TaotaoResult(status, msg, null);
43. }

45. public TaotaoResult(Integer status, String msg, Object data) {
46. this.status = status;
47. this.msg = msg;
48. this.data = data;
49. }

51. public TaotaoResult(Object data) {
52. this.status = 200;
53. this.msg = "OK";
54. this.data = data;
55. }

57. // public Boolean isOK() {
58. // return this.status == 200;
59. // }

61. public Integer getStatus() {
62. return status;
63. }

65. public void setStatus(Integer status) {
66. this.status = status;
67. }

69. public String getMsg() {
70. return msg;
71. }

73. public void setMsg(String msg) {
74. this.msg = msg;
75. }

77. public Object getData() {
78. return data;
79. }

81. public void setData(Object data) {
82. this.data = data;
83. }

85. /**
86. * 将json结果集转化为TaotaoResult对象
87. *
88. * @param jsonData json数据
89. * @param clazz TaotaoResult中的object类型
90. * @return
91. */
92. public static TaotaoResult formatToPojo(String jsonData, Class<?> clazz) {
93. try {
94. if (clazz == null) {
95. return MAPPER.readValue(jsonData, TaotaoResult.class);
96. }
97. JsonNode jsonNode = MAPPER.readTree(jsonData);
98. JsonNode data = jsonNode.get("data");
99. Object obj = null;
100. if (clazz != null) {
101. if (data.isObject()) {
102. obj = MAPPER.readValue(data.traverse(), clazz);
103. } else if (data.isTextual()) {
104. obj = MAPPER.readValue(data.asText(), clazz);
105. }
106. }
107. return build(jsonNode.get("status").intValue(), jsonNode.get("msg").asText(), obj);
108. } catch (Exception e) {
109. return null;
110. }
111. }

113. /**
114. * 没有object对象的转化
115. *
116. * @param json
117. * @return
118. */
119. public static TaotaoResult format(String json) {
120. try {
121. return MAPPER.readValue(json, TaotaoResult.class);
122. } catch (Exception e) {
123. e.printStackTrace();
124. }
125. return null;
126. }

128. /**
129. * Object是集合转化
130. *
131. * @param jsonData json数据
132. * @param clazz 集合中的类型
133. * @return
134. */
135. public static TaotaoResult formatToList(String jsonData, Class<?> clazz) {
136. try {
137. JsonNode jsonNode = MAPPER.readTree(jsonData);
138. JsonNode data = jsonNode.get("data");
139. Object obj = null;
140. if (data.isArray() && data.size() > 0) {
141. obj = MAPPER.readValue(data.traverse(),
142. MAPPER.getTypeFactory().constructCollectionType(List.class, clazz));
143. }
144. return build(jsonNode.get("status").intValue(), jsonNode.get("msg").asText(), obj);
145. } catch (Exception e) {
146. return null;
147. }
148. }

150. }

##11.jedis操作

1.  package com.taotao.jedis;

3.  public interface JedisClient {

5.  String set(String key, String value);
6.  String get(String key);
7.  Boolean exists(String key);
8.  Long expire(String key, int seconds);
9.  Long ttl(String key);
10.  Long incr(String key);
11.  Long hset(String key, String field, String value);
12.  String hget(String key, String field);
13.  Long hdel(String key, String... field);
14.  }

1.  package com.taotao.jedis;

3.  import org.springframework.beans.factory.annotation.Autowired;

5.  import redis.clients.jedis.JedisCluster;

7.  public class JedisClientCluster implements JedisClient {

9.  @Autowired
10.  private JedisCluster jedisCluster;

12.  @Override
13.  public String set(String key, String value) {
14.  return jedisCluster.set(key, value);
15.  }

17.  @Override
18.  public String get(String key) {
19.  return jedisCluster.get(key);
20.  }

22.  @Override
23.  public Boolean exists(String key) {
24.  return jedisCluster.exists(key);
25.  }

27.  @Override
28.  public Long expire(String key, int seconds) {
29.  return jedisCluster.expire(key, seconds);
30.  }

32.  @Override
33.  public Long ttl(String key) {
34.  return jedisCluster.ttl(key);
35.  }

37.  @Override
38.  public Long incr(String key) {
39.  return jedisCluster.incr(key);
40.  }

42.  @Override
43.  public Long hset(String key, String field, String value) {
44.  return jedisCluster.hset(key, field, value);
45.  }

47.  @Override
48.  public String hget(String key, String field) {
49.  return jedisCluster.hget(key, field);
50.  }

52.  @Override
53.  public Long hdel(String key, String... field) {
54.  return jedisCluster.hdel(key, field);
55.  }

57.  }

1.  package com.taotao.jedis;

4.  import org.springframework.beans.factory.annotation.Autowired;

7.  import redis.clients.jedis.Jedis;
8.  import redis.clients.jedis.JedisPool;

11.  public class JedisClientPool implements JedisClient {

13.  @Autowired
14.  private JedisPool jedisPool;

17.  @Override
18.  public String set(String key, String value) {
19.  Jedis jedis = jedisPool.getResource();
20.  String result = jedis.set(key, value);
21.  jedis.close();
22.  return result;
23.  }

26.  @Override
27.  public String get(String key) {
28.  Jedis jedis = jedisPool.getResource();
29.  String result = jedis.get(key);
30.  jedis.close();
31.  return result;
32.  }

35.  @Override
36.  public Boolean exists(String key) {
37.  Jedis jedis = jedisPool.getResource();
38.  Boolean result = jedis.exists(key);
39.  jedis.close();
40.  return result;
41.  }

44.  @Override
45.  public Long expire(String key, int seconds) {
46.  Jedis jedis = jedisPool.getResource();
47.  Long result = jedis.expire(key, seconds);
48.  jedis.close();
49.  return result;
50.  }

53.  @Override
54.  public Long ttl(String key) {
55.  Jedis jedis = jedisPool.getResource();
56.  Long result = jedis.ttl(key);
57.  jedis.close();
58.  return result;
59.  }

62.  @Override
63.  public Long incr(String key) {
64.  Jedis jedis = jedisPool.getResource();
65.  Long result = jedis.incr(key);
66.  jedis.close();
67.  return result;
68.  }

71.  @Override
72.  public Long hset(String key, String field, String value) {
73.  Jedis jedis = jedisPool.getResource();
74.  Long result = jedis.hset(key, field, value);
75.  jedis.close();
76.  return result;
77.  }

80.  @Override
81.  public String hget(String key, String field) {
82.  Jedis jedis = jedisPool.getResource();
83.  String result = jedis.hget(key, field);
84.  jedis.close();
85.  return result;
86.  }

89.  @Override
90.  public Long hdel(String key, String... field) {
91.  Jedis jedis = jedisPool.getResource();
92.  Long result = jedis.hdel(key, field);
93.  jedis.close();
94.  return result;
95.  }

98.  }

本文作者：[一个小迷糊]

    [阅读原文]([http://click.aliyun.com/m/50526/]

    本文为云栖社区原创内容，未经允许不得转载。

----------------------------
原文链接:https://www.jianshu.com/p/6a372ee8bfb9

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[这个贴子最后由 flybird 在 2020-12-27 22:15:12 重新编辑]

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