整理收集的一些常用java工具类

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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.  * <p>Title: pojoToJson</p> 
21.  * <p>Description: </p> 
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.  * <p>Title: jsonToList</p> 
55.  * <p>Description: </p> 
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.  * <p>Title: uploadFile</p> 
31.  * <p>Description: </p> 
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.  * <p>Title: uploadFile</p> 
54.  * <p>Description: </p> 
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.  <span style="font-size:14px;font-weight:normal;">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.  }</span>  

# ![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.  * <p>Title: EasyUIResult</p> 
8.  * <p>Description: </p> 
9.  * <p>Company: www.itcast.com</p>  
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.  * <p>Title: FtpUtil</p> 
19.  * <p>Description: </p> 
20.  * <p>Company: www.itcast.com</p>  
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.  * <p>Title: IDUtils</p> 
8.  * <p>Description: </p> 
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×××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×××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.  * <p>Title: PictureResult</p> 
5.  * <p>Description: </p> 
6.  * <p>Company: www.itcast.com</p>  
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.  }

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