Java使用RSA加密解密签名及校验_JAVA_编程开发_程序员俱乐部

由于项目要用到非对称加密解密签名校验什么的，于是参考《Java加密解密的艺术》写一个RSA进行加密解密签名及校验的Demo，代码很简单，特此分享！

RSA加密解密类：

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class="dp-j" style="border: none; color: #5c5c5c; margin-bottom: 1px !important; margin-left: 45px !important; background-color: #ffffff;">
1. package?com.ihep;??
2. ??
3. import?java.io.BufferedReader;??
4. import?java.io.BufferedWriter;??
5. import?java.io.FileReader;??
6. import?java.io.FileWriter;??
7. import?java.io.IOException;??
8. import?java.security.InvalidKeyException;??
9. import?java.security.KeyFactory;??
10. import?java.security.KeyPair;??
11. import?java.security.KeyPairGenerator;??
12. import?java.security.NoSuchAlgorithmException;??
13. import?java.security.SecureRandom;??
14. ??
15. import?java.security.interfaces.RSAPrivateKey;??
16. import?java.security.interfaces.RSAPublicKey;??
17. import?java.security.spec.InvalidKeySpecException;??
18. import?java.security.spec.PKCS8EncodedKeySpec;??
19. import?java.security.spec.X509EncodedKeySpec;??
20. ??
21. import?javax.crypto.BadPaddingException;??
22. import?javax.crypto.Cipher;??
23. import?javax.crypto.IllegalBlockSizeException;??
24. import?javax.crypto.NoSuchPaddingException;??
25. ??
26. import?com.fcplay.Base64;??
27. ??
28. public?class?RSAEncrypt?{??
29. ????/**?
30. ?????*?字节数据转字符串专用集合?
31. ?????*/??
32. ????private?static?final?char[]?HEX_CHAR?=?{?'0',?'1',?'2',?'3',?'4',?'5',?'6',??
33. ????????????'7',?'8',?'9',?'a',?'b',?'c',?'d',?'e',?'f'?};??
34. ??
35. ????/**?
36. ?????*?随机生成密钥对?
37. ?????*/??
38. ????public?static?void?genKeyPair(String?filePath)?{??
39. ????????//?KeyPairGenerator类用于生成公钥和私钥对，基于RSA算法生成对象??
40. ????????KeyPairGenerator?keyPairGen?=?null;??
41. ????????try?{??
42. ????????????keyPairGen?=?KeyPairGenerator.getInstance("RSA");??
43. ????????}?catch?(NoSuchAlgorithmException?e)?{??
44. ????????????//?TODO?Auto-generated?catch?block??
45. ????????????e.printStackTrace();??
46. ????????}??
47. ????????//?初始化密钥对生成器，密钥大小为96-1024位??
48. ????????keyPairGen.initialize(1024,new?SecureRandom());??
49. ????????//?生成一个密钥对，保存在keyPair中??
50. ????????KeyPair?keyPair?=?keyPairGen.generateKeyPair();??
51. ????????//?得到私钥??
52. ????????RSAPrivateKey?privateKey?=?(RSAPrivateKey)?keyPair.getPrivate();??
53. ????????//?得到公钥??
54. ????????RSAPublicKey?publicKey?=?(RSAPublicKey)?keyPair.getPublic();??
55. ????????try?{??
56. ????????????//?得到公钥字符串??
57. ????????????String?publicKeyString?=?Base64.encode(publicKey.getEncoded());??
58. ????????????//?得到私钥字符串??
59. ????????????String?privateKeyString?=?Base64.encode(privateKey.getEncoded());??
60. ????????????//?将密钥对写入到文件??
61. ????????????FileWriter?pubfw?=?new?FileWriter(filePath?+?"/publicKey.keystore");??
62. ????????????FileWriter?prifw?=?new?FileWriter(filePath?+?"/privateKey.keystore");??
63. ????????????BufferedWriter?pubbw?=?new?BufferedWriter(pubfw);??
64. ????????????BufferedWriter?pribw?=?new?BufferedWriter(prifw);??
65. ????????????pubbw.write(publicKeyString);??
66. ????????????pribw.write(privateKeyString);??
67. ????????????pubbw.flush();??
68. ????????????pubbw.close();??
69. ????????????pubfw.close();??
70. ????????????pribw.flush();??
71. ????????????pribw.close();??
72. ????????????prifw.close();??
73. ????????}?catch?(Exception?e)?{??
74. ????????????e.printStackTrace();??
75. ????????}??
76. ????}??
77. ??
78. ????/**?
79. ?????*?从文件中输入流中加载公钥?
80. ?????*??
81. ?????*?@param?in?
82. ?????*????????????公钥输入流?
83. ?????*?@throws?Exception?
84. ?????*?????????????加载公钥时产生的异常?
85. ?????*/??
86. ????public?static?String?loadPublicKeyByFile(String?path)?throws?Exception?{??
87. ????????try?{??
88. ????????????BufferedReader?br?=?new?BufferedReader(new?FileReader(path??
89. ????????????????????+?"/publicKey.keystore"));??
90. ????????????String?readLine?=?null;??
91. ????????????StringBuilder?sb?=?new?StringBuilder();??
92. ????????????while?((readLine?=?br.readLine())?!=?null)?{??
93. ????????????????sb.append(readLine);??
94. ????????????}??
95. ????????????br.close();??
96. ????????????return?sb.toString();??
97. ????????}?catch?(IOException?e)?{??
98. ????????????throw?new?Exception("公钥数据流读取错误");??
99. ????????}?catch?(NullPointerException?e)?{??
100. ????????????throw?new?Exception("公钥输入流为空");??
101. ????????}??
102. ????}??
103. ??
104. ????/**?
105. ?????*?从字符串中加载公钥?
106. ?????*??
107. ?????*?@param?publicKeyStr?
108. ?????*????????????公钥数据字符串?
109. ?????*?@throws?Exception?
110. ?????*?????????????加载公钥时产生的异常?
111. ?????*/??
112. ????public?static?RSAPublicKey?loadPublicKeyByStr(String?publicKeyStr)??
113. ????????????throws?Exception?{??
114. ????????try?{??
115. ????????????byte[]?buffer?=?Base64.decode(publicKeyStr);??
116. ????????????KeyFactory?keyFactory?=?KeyFactory.getInstance("RSA");??
117. ????????????X509EncodedKeySpec?keySpec?=?new?X509EncodedKeySpec(buffer);??
118. ????????????return?(RSAPublicKey)?keyFactory.generatePublic(keySpec);??
119. ????????}?catch?(NoSuchAlgorithmException?e)?{??
120. ????????????throw?new?Exception("无此算法");??
121. ????????}?catch?(InvalidKeySpecException?e)?{??
122. ????????????throw?new?Exception("公钥非法");??
123. ????????}?catch?(NullPointerException?e)?{??
124. ????????????throw?new?Exception("公钥数据为空");??
125. ????????}??
126. ????}??
127. ??
128. ????/**?
129. ?????*?从文件中加载私钥?
130. ?????*??
131. ?????*?@param?keyFileName?
132. ?????*????????????私钥文件名?
133. ?????*?@return?是否成功?
134. ?????*?@throws?Exception?
135. ?????*/??
136. ????public?static?String?loadPrivateKeyByFile(String?path)?throws?Exception?{??
137. ????????try?{??
138. ????????????BufferedReader?br?=?new?BufferedReader(new?FileReader(path??
139. ????????????????????+?"/privateKey.keystore"));??
140. ????????????String?readLine?=?null;??
141. ????????????StringBuilder?sb?=?new?StringBuilder();??
142. ????????????while?((readLine?=?br.readLine())?!=?null)?{??
143. ????????????????sb.append(readLine);??
144. ????????????}??
145. ????????????br.close();??
146. ????????????return?sb.toString();??
147. ????????}?catch?(IOException?e)?{??
148. ????????????throw?new?Exception("私钥数据读取错误");??
149. ????????}?catch?(NullPointerException?e)?{??
150. ????????????throw?new?Exception("私钥输入流为空");??
151. ????????}??
152. ????}??
153. ??
154. ????public?static?RSAPrivateKey?loadPrivateKeyByStr(String?privateKeyStr)??
155. ????????????throws?Exception?{??
156. ????????try?{??
157. ????????????byte[]?buffer?=?Base64.decode(privateKeyStr);??
158. ????????????PKCS8EncodedKeySpec?keySpec?=?new?PKCS8EncodedKeySpec(buffer);??
159. ????????????KeyFactory?keyFactory?=?KeyFactory.getInstance("RSA");??
160. ????????????return?(RSAPrivateKey)?keyFactory.generatePrivate(keySpec);??
161. ????????}?catch?(NoSuchAlgorithmException?e)?{??
162. ????????????throw?new?Exception("无此算法");??
163. ????????}?catch?(InvalidKeySpecException?e)?{??
164. ????????????throw?new?Exception("私钥非法");??
165. ????????}?catch?(NullPointerException?e)?{??
166. ????????????throw?new?Exception("私钥数据为空");??
167. ????????}??
168. ????}??
169. ??
170. ????/**?
171. ?????*?公钥加密过程?
172. ?????*??
173. ?????*?@param?publicKey?
174. ?????*????????????公钥?
175. ?????*?@param?plainTextData?
176. ?????*????????????明文数据?
177. ?????*?@return?
178. ?????*?@throws?Exception?
179. ?????*?????????????加密过程中的异常信息?
180. ?????*/??
181. ????public?static?byte[]?encrypt(RSAPublicKey?publicKey,?byte[]?plainTextData)??
182. ????????????throws?Exception?{??
183. ????????if?(publicKey?==?null)?{??
184. ????????????throw?new?Exception("加密公钥为空,?请设置");??
185. ????????}??
186. ????????Cipher?cipher?=?null;??
187. ????????try?{??
188. ????????????//?使用默认RSA??
189. ????????????cipher?=?Cipher.getInstance("RSA");??
190. ????????????//?cipher=?Cipher.getInstance("RSA",?new?BouncyCastleProvider());??
191. ????????????cipher.init(Cipher.ENCRYPT_MODE,?publicKey);??
192. ????????????byte[]?output?=?cipher.doFinal(plainTextData);??
193. ????????????return?output;??
194. ????????}?catch?(NoSuchAlgorithmException?e)?{??
195. ????????????throw?new?Exception("无此加密算法");??
196. ????????}?catch?(NoSuchPaddingException?e)?{??
197. ????????????e.printStackTrace();??
198. ????????????return?null;??
199. ????????}?catch?(InvalidKeyException?e)?{??
200. ????????????throw?new?Exception("加密公钥非法,请检查");??
201. ????????}?catch?(IllegalBlockSizeException?e)?{??
202. ????????????throw?new?Exception("明文长度非法");??
203. ????????}?catch?(BadPaddingException?e)?{??
204. ????????????throw?new?Exception("明文数据已损坏");??
205. ????????}??
206. ????}??
207. ??
208. ????/**?
209. ?????*?私钥加密过程?
210. ?????*??
211. ?????*?@param?privateKey?
212. ?????*????????????私钥?
213. ?????*?@param?plainTextData?
214. ?????*????????????明文数据?
215. ?????*?@return?
216. ?????*?@throws?Exception?
217. ?????*?????????????加密过程中的异常信息?
218. ?????*/??
219. ????public?static?byte[]?encrypt(RSAPrivateKey?privateKey,?byte[]?plainTextData)??
220. ????????????throws?Exception?{??
221. ????????if?(privateKey?==?null)?{??
222. ????????????throw?new?Exception("加密私钥为空,?请设置");??
223. ????????}??
224. ????????Cipher?cipher?=?null;??
225. ????????try?{??
226. ????????????//?使用默认RSA??
227. ????????????cipher?=?Cipher.getInstance("RSA");??
228. ????????????cipher.init(Cipher.ENCRYPT_MODE,?privateKey);??
229. ????????????byte[]?output?=?cipher.doFinal(plainTextData);??
230. ????????????return?output;??
231. ????????}?catch?(NoSuchAlgorithmException?e)?{??
232. ????????????throw?new?Exception("无此加密算法");??
233. ????????}?catch?(NoSuchPaddingException?e)?{??
234. ????????????e.printStackTrace();??
235. ????????????return?null;??
236. ????????}?catch?(InvalidKeyException?e)?{??
237. ????????????throw?new?Exception("加密私钥非法,请检查");??
238. ????????}?catch?(IllegalBlockSizeException?e)?{??
239. ????????????throw?new?Exception("明文长度非法");??
240. ????????}?catch?(BadPaddingException?e)?{??
241. ????????????throw?new?Exception("明文数据已损坏");??
242. ????????}??
243. ????}??
244. ??
245. ????/**?
246. ?????*?私钥解密过程?
247. ?????*??
248. ?????*?@param?privateKey?
249. ?????*????????????私钥?
250. ?????*?@param?cipherData?
251. ?????*????????????密文数据?
252. ?????*?@return?明文?
253. ?????*?@throws?Exception?
254. ?????*?????????????解密过程中的异常信息?
255. ?????*/??
256. ????public?static?byte[]?decrypt(RSAPrivateKey?privateKey,?byte[]?cipherData)??
257. ????????????throws?Exception?{??
258. ????????if?(privateKey?==?null)?{??
259. ????????????throw?new?Exception("解密私钥为空,?请设置");??
260. ????????}??
261. ????????Cipher?cipher?=?null;??
262. ????????try?{??
263. ????????????//?使用默认RSA??
264. ????????????cipher?=?Cipher.getInstance("RSA");??
265. ????????????//?cipher=?Cipher.getInstance("RSA",?new?BouncyCastleProvider());??
266. ????????????cipher.init(Cipher.DECRYPT_MODE,?privateKey);??
267. ????????????byte[]?output?=?cipher.doFinal(cipherData);??
268. ????????????return?output;??
269. ????????}?catch?(NoSuchAlgorithmException?e)?{??
270. ????????????throw?new?Exception("无此解密算法");??
271. ????????}?catch?(NoSuchPaddingException?e)?{??
272. ????????????e.printStackTrace();??
273. ????????????return?null;??
274. ????????}?catch?(InvalidKeyException?e)?{??
275. ????????????throw?new?Exception("解密私钥非法,请检查");??
276. ????????}?catch?(IllegalBlockSizeException?e)?{??
277. ????????????throw?new?Exception("密文长度非法");??
278. ????????}?catch?(BadPaddingException?e)?{??
279. ????????????throw?new?Exception("密文数据已损坏");??
280. ????????}??
281. ????}??
282. ??
283. ????/**?
284. ?????*?公钥解密过程?
285. ?????*??
286. ?????*?@param?publicKey?
287. ?????*????????????公钥?
288. ?????*?@param?cipherData?
289. ?????*????????????密文数据?
290. ?????*?@return?明文?
291. ?????*?@throws?Exception?
292. ?????*?????????????解密过程中的异常信息?
293. ?????*/??
294. ????public?static?byte[]?decrypt(RSAPublicKey?publicKey,?byte[]?cipherData)??
295. ????????????throws?Exception?{??
296. ????????if?(publicKey?==?null)?{??
297. ????????????throw?new?Exception("解密公钥为空,?请设置");??
298. ????????}??
299. ????????Cipher?cipher?=?null;??
300. ????????try?{??
301. ????????????//?使用默认RSA??
302. ????????????cipher?=?Cipher.getInstance("RSA");??
303. ????????????//?cipher=?Cipher.getInstance("RSA",?new?BouncyCastleProvider());??
304. ????????????cipher.init(Cipher.DECRYPT_MODE,?publicKey);??
305. ????????????byte[]?output?=?cipher.doFinal(cipherData);??
306. ????????????return?output;??
307. ????????}?catch?(NoSuchAlgorithmException?e)?{??
308. ????????????throw?new?Exception("无此解密算法");??
309. ????????}?catch?(NoSuchPaddingException?e)?{??
310. ????????????e.printStackTrace();??
311. ????????????return?null;??
312. ????????}?catch?(InvalidKeyException?e)?{??
313. ????????????throw?new?Exception("解密公钥非法,请检查");??
314. ????????}?catch?(IllegalBlockSizeException?e)?{??
315. ????????????throw?new?Exception("密文长度非法");??
316. ????????}?catch?(BadPaddingException?e)?{??
317. ????????????throw?new?Exception("密文数据已损坏");??
318. ????????}??
319. ????}??
320. ??
321. ????/**?
322. ?????*?字节数据转十六进制字符串?
323. ?????*??
324. ?????*?@param?data?
325. ?????*????????????输入数据?
326. ?????*?@return?十六进制内容?
327. ?????*/??
328. ????public?static?String?byteArrayToString(byte[]?data)?{??
329. ????????StringBuilder?stringBuilder?=?new?StringBuilder();??
330. ????????for?(int?i?=?0;?i?<?data.length;?i++)?{??
331. ????????????//?取出字节的高四位?作为索引得到相应的十六进制标识符?注意无符号右移??
332. ????????????stringBuilder.append(HEX_CHAR[(data[i]?&?0xf0)?>>>?4]);??
333. ????????????//?取出字节的低四位?作为索引得到相应的十六进制标识符??
334. ????????????stringBuilder.append(HEX_CHAR[(data[i]?&?0x0f)]);??
335. ????????????if?(i?<?data.length?-?1)?{??
336. ????????????????stringBuilder.append('?');??
337. ????????????}??
338. ????????}??
339. ????????return?stringBuilder.toString();??
340. ????}??
341. }??

?

?

签名及校验类：

?

1. package?com.ihep;??
2. ??
3. import?java.security.KeyFactory;??
4. import?java.security.PrivateKey;??
5. import?java.security.PublicKey;??
6. import?java.security.spec.PKCS8EncodedKeySpec;??
7. import?java.security.spec.X509EncodedKeySpec;??
8. ??
9. ??
10. ??
11. /**?
12. ?*?RSA签名验签类?
13. ?*/??
14. public?class?RSASignature{??
15. ??????
16. ????/**?
17. ?????*?签名算法?
18. ?????*/??
19. ????public?static?final?String?SIGN_ALGORITHMS?=?"SHA1WithRSA";??
20. ??
21. ????/**?
22. ????*?RSA签名?
23. ????*?@param?content?待签名数据?
24. ????*?@param?privateKey?商户私钥?
25. ????*?@param?encode?字符集编码?
26. ????*?@return?签名值?
27. ????*/??
28. ????public?static?String?sign(String?content,?String?privateKey,?String?encode)??
29. ????{??
30. ????????try???
31. ????????{??
32. ????????????PKCS8EncodedKeySpec?priPKCS8????=?new?PKCS8EncodedKeySpec(?Base64.decode(privateKey)?);???
33. ??????????????
34. ????????????KeyFactory?keyf?????????????????=?KeyFactory.getInstance("RSA");??
35. ????????????PrivateKey?priKey???????????????=?keyf.generatePrivate(priPKCS8);??
36. ??
37. ????????????java.security.Signature?signature?=?java.security.Signature.getInstance(SIGN_ALGORITHMS);??
38. ??
39. ????????????signature.initSign(priKey);??
40. ????????????signature.update(?content.getBytes(encode));??
41. ??
42. ????????????byte[]?signed?=?signature.sign();??
43. ??????????????
44. ????????????return?Base64.encode(signed);??
45. ????????}??
46. ????????catch?(Exception?e)???
47. ????????{??
48. ????????????e.printStackTrace();??
49. ????????}??
50. ??????????
51. ????????return?null;??
52. ????}??
53. ??????
54. ????public?static?String?sign(String?content,?String?privateKey)??
55. ????{??
56. ????????try???
57. ????????{??
58. ????????????PKCS8EncodedKeySpec?priPKCS8????=?new?PKCS8EncodedKeySpec(?Base64.decode(privateKey)?);???
59. ????????????KeyFactory?keyf?=?KeyFactory.getInstance("RSA");??
60. ????????????PrivateKey?priKey?=?keyf.generatePrivate(priPKCS8);??
61. ????????????java.security.Signature?signature?=?java.security.Signature.getInstance(SIGN_ALGORITHMS);??
62. ????????????signature.initSign(priKey);??
63. ????????????signature.update(?content.getBytes());??
64. ????????????byte[]?signed?=?signature.sign();??
65. ????????????return?Base64.encode(signed);??
66. ????????}??
67. ????????catch?(Exception?e)???
68. ????????{??
69. ????????????e.printStackTrace();??
70. ????????}??
71. ????????return?null;??
72. ????}??
73. ??????
74. ????/**?
75. ????*?RSA验签名检查?
76. ????*?@param?content?待签名数据?
77. ????*?@param?sign?签名值?
78. ????*?@param?publicKey?分配给开发商公钥?
79. ????*?@param?encode?字符集编码?
80. ????*?@return?布尔值?
81. ????*/??
82. ????public?static?boolean?doCheck(String?content,?String?sign,?String?publicKey,String?encode)??
83. ????{??
84. ????????try???
85. ????????{??
86. ????????????KeyFactory?keyFactory?=?KeyFactory.getInstance("RSA");??
87. ????????????byte[]?encodedKey?=?Base64.decode(publicKey);??
88. ????????????PublicKey?pubKey?=?keyFactory.generatePublic(new?X509EncodedKeySpec(encodedKey));??
89. ??
90. ??????????
91. ????????????java.security.Signature?signature?=?java.security.Signature??
92. ????????????.getInstance(SIGN_ALGORITHMS);??
93. ??????????
94. ????????????signature.initVerify(pubKey);??
95. ????????????signature.update(?content.getBytes(encode)?);??
96. ??????????
97. ????????????boolean?bverify?=?signature.verify(?Base64.decode(sign)?);??
98. ????????????return?bverify;??
99. ??????????????
100. ????????}???
101. ????????catch?(Exception?e)???
102. ????????{??
103. ????????????e.printStackTrace();??
104. ????????}??
105. ??????????
106. ????????return?false;??
107. ????}??
108. ??????
109. ????public?static?boolean?doCheck(String?content,?String?sign,?String?publicKey)??
110. ????{??
111. ????????try???
112. ????????{??
113. ????????????KeyFactory?keyFactory?=?KeyFactory.getInstance("RSA");??
114. ????????????byte[]?encodedKey?=?Base64.decode(publicKey);??
115. ????????????PublicKey?pubKey?=?keyFactory.generatePublic(new?X509EncodedKeySpec(encodedKey));??
116. ??
117. ??????????
118. ????????????java.security.Signature?signature?=?java.security.Signature??
119. ????????????.getInstance(SIGN_ALGORITHMS);??
120. ??????????
121. ????????????signature.initVerify(pubKey);??
122. ????????????signature.update(?content.getBytes()?);??
123. ??????????
124. ????????????boolean?bverify?=?signature.verify(?Base64.decode(sign)?);??
125. ????????????return?bverify;??
126. ??????????????
127. ????????}???
128. ????????catch?(Exception?e)???
129. ????????{??
130. ????????????e.printStackTrace();??
131. ????????}??
132. ??????????
133. ????????return?false;??
134. ????}??
135. ??????
136. }??

?

再来一个Base64的类，当然你也可以用commons-codec-1.9.jar

?

1. package?com.ihep;??
2. ??
3. public?final?class?Base64?{??
4. ??
5. ????static?private?final?int?????BASELENGTH???????????=?128;??
6. ????static?private?final?int?????LOOKUPLENGTH?????????=?64;??
7. ????static?private?final?int?????TWENTYFOURBITGROUP???=?24;??
8. ????static?private?final?int?????EIGHTBIT?????????????=?8;??
9. ????static?private?final?int?????SIXTEENBIT???????????=?16;??
10. ????static?private?final?int?????FOURBYTE?????????????=?4;??
11. ????static?private?final?int?????SIGN?????????????????=?-128;??
12. ????static?private?final?char????PAD??????????????????=?'=';??
13. ????static?private?final?boolean?fDebug???????????????=?false;??
14. ????static?final?private?byte[]??base64Alphabet???????=?new?byte[BASELENGTH];??
15. ????static?final?private?char[]??lookUpBase64Alphabet?=?new?char[LOOKUPLENGTH];??
16. ??
17. ????static?{??
18. ????????for?(int?i?=?0;?i?<?BASELENGTH;?++i)?{??
19. ????????????base64Alphabet[i]?=?-1;??
20. ????????}??
21. ????????for?(int?i?=?'Z';?i?>=?'A';?i--)?{??
22. ????????????base64Alphabet[i]?=?(byte)?(i?-?'A');??
23. ????????}??
24. ????????for?(int?i?=?'z';?i?>=?'a';?i--)?{??
25. ????????????base64Alphabet[i]?=?(byte)?(i?-?'a'?+?26);??
26. ????????}??
27. ??
28. ????????for?(int?i?=?'9';?i?>=?'0';?i--)?{??
29. ????????????base64Alphabet[i]?=?(byte)?(i?-?'0'?+?52);??
30. ????????}??
31. ??
32. ????????base64Alphabet['+']?=?62;??
33. ????????base64Alphabet['/']?=?63;??
34. ??
35. ????????for?(int?i?=?0;?i?<=?25;?i++)?{??
36. ????????????lookUpBase64Alphabet[i]?=?(char)?('A'?+?i);??
37. ????????}??
38. ??
39. ????????for?(int?i?=?26,?j?=?0;?i?<=?51;?i++,?j++)?{??
40. ????????????lookUpBase64Alphabet[i]?=?(char)?('a'?+?j);??
41. ????????}??
42. ??
43. ????????for?(int?i?=?52,?j?=?0;?i?<=?61;?i++,?j++)?{??
44. ????????????lookUpBase64Alphabet[i]?=?(char)?('0'?+?j);??
45. ????????}??
46. ????????lookUpBase64Alphabet[62]?=?(char)?'+';??
47. ????????lookUpBase64Alphabet[63]?=?(char)?'/';??
48. ??
49. ????}??
50. ??
51. ????private?static?boolean?isWhiteSpace(char?octect)?{??
52. ????????return?(octect?==?0x20?||?octect?==?0xd?||?octect?==?0xa?||?octect?==?0x9);??
53. ????}??
54. ??
55. ????private?static?boolean?isPad(char?octect)?{??
56. ????????return?(octect?==?PAD);??
57. ????}??
58. ??
59. ????private?static?boolean?isData(char?octect)?{??
60. ????????return?(octect?<?BASELENGTH?&&?base64Alphabet[octect]?!=?-1);??
61. ????}??
62. ??
63. ????/**?
64. ?????*?Encodes?hex?octects?into?Base64?
65. ?????*?
66. ?????*?@param?binaryData?Array?containing?binaryData?
67. ?????*?@return?Encoded?Base64?array?
68. ?????*/??
69. ????public?static?String?encode(byte[]?binaryData)?{??
70. ??
71. ????????if?(binaryData?==?null)?{??
72. ????????????return?null;??
73. ????????}??
74. ??
75. ????????int?lengthDataBits?=?binaryData.length?*?EIGHTBIT;??
76. ????????if?(lengthDataBits?==?0)?{??
77. ????????????return?"";??
78. ????????}??
79. ??
80. ????????int?fewerThan24bits?=?lengthDataBits?%?TWENTYFOURBITGROUP;??
81. ????????int?numberTriplets?=?lengthDataBits?/?TWENTYFOURBITGROUP;??
82. ????????int?numberQuartet?=?fewerThan24bits?!=?0???numberTriplets?+?1?:?numberTriplets;??
83. ????????char?encodedData[]?=?null;??
84. ??
85. ????????encodedData?=?new?char[numberQuartet?*?4];??
86. ??
87. ????????byte?k?=?0,?l?=?0,?b1?=?0,?b2?=?0,?b3?=?0;??
88. ??
89. ????????int?encodedIndex?=?0;??
90. ????????int?dataIndex?=?0;??
91. ????????if?(fDebug)?{??
92. ????????????System.out.println("number?of?triplets?=?"?+?numberTriplets);??
93. ????????}??
94. ??
95. ????????for?(int?i?=?0;?i?<?numberTriplets;?i++)?{??
96. ????????????b1?=?binaryData[dataIndex++];??
97. ????????????b2?=?binaryData[dataIndex++];??
98. ????????????b3?=?binaryData[dataIndex++];??
99. ??
100. ????????????if?(fDebug)?{??
101. ????????????????System.out.println("b1=?"?+?b1?+?",?b2=?"?+?b2?+?",?b3=?"?+?b3);??
102. ????????????}??
103. ??
104. ????????????l?=?(byte)?(b2?&?0x0f);??
105. ????????????k?=?(byte)?(b1?&?0x03);??
106. ??
107. ????????????byte?val1?=?((b1?&?SIGN)?==?0)???(byte)?(b1?>>?2)?:?(byte)?((b1)?>>?2?^?0xc0);??
108. ????????????byte?val2?=?((b2?&?SIGN)?==?0)???(byte)?(b2?>>?4)?:?(byte)?((b2)?>>?4?^?0xf0);??
109. ????????????byte?val3?=?((b3?&?SIGN)?==?0)???(byte)?(b3?>>?6)?:?(byte)?((b3)?>>?6?^?0xfc);??
110. ??
111. ????????????if?(fDebug)?{??
112. ????????????????System.out.println("val2?=?"?+?val2);??
113. ????????????????System.out.println("k4???=?"?+?(k?<<?4));??
114. ????????????????System.out.println("vak??=?"?+?(val2?|?(k?<<?4)));??
115. ????????????}??
116. ??
117. ????????????encodedData[encodedIndex++]?=?lookUpBase64Alphabet[val1];??
118. ????????????encodedData[encodedIndex++]?=?lookUpBase64Alphabet[val2?|?(k?<<?4)];??
119. ????????????encodedData[encodedIndex++]?=?lookUpBase64Alphabet[(l?<<?2)?|?val3];??
120. ????????????encodedData[encodedIndex++]?=?lookUpBase64Alphabet[b3?&?0x3f];??
121. ????????}??
122. ??
123. ????????//?form?integral?number?of?6-bit?groups??
124. ????????if?(fewerThan24bits?==?EIGHTBIT)?{??
125. ????????????b1?=?binaryData[dataIndex];??
126. ????????????k?=?(byte)?(b1?&?0x03);??
127. ????????????if?(fDebug)?{??
128. ????????????????System.out.println("b1="?+?b1);??
129. ????????????????System.out.println("b1<<2?=?"?+?(b1?>>?2));??
130. ????????????}??
131. ????????????byte?val1?=?((b1?&?SIGN)?==?0)???(byte)?(b1?>>?2)?:?(byte)?((b1)?>>?2?^?0xc0);??
132. ????????????encodedData[encodedIndex++]?=?lookUpBase64Alphabet[val1];??
133. ????????????encodedData[encodedIndex++]?=?lookUpBase64Alphabet[k?<<?4];??
134. ????????????encodedData[encodedIndex++]?=?PAD;??
135. ????????????encodedData[encodedIndex++]?=?PAD;??
136. ????????}?else?if?(fewerThan24bits?==?SIXTEENBIT)?{??
137. ????????????b1?=?binaryData[dataIndex];??
138. ????????????b2?=?binaryData[dataIndex?+?1];??
139. ????????????l?=?(byte)?(b2?&?0x0f);??
140. ????????????k?=?(byte)?(b1?&?0x03);??
141. ??
142. ????????????byte?val1?=?((b1?&?SIGN)?==?0)???(byte)?(b1?>>?2)?:?(byte)?((b1)?>>?2?^?0xc0);??
143. ????????????byte?val2?=?((b2?&?SIGN)?==?0)???(byte)?(b2?>>?4)?:?(byte)?((b2)?>>?4?^?0xf0);??
144. ??
145. ????????????encodedData[encodedIndex++]?=?lookUpBase64Alphabet[val1];??
146. ????????????encodedData[encodedIndex++]?=?lookUpBase64Alphabet[val2?|?(k?<<?4)];??
147. ????????????encodedData[encodedIndex++]?=?lookUpBase64Alphabet[l?<<?2];??
148. ????????????encodedData[encodedIndex++]?=?PAD;??
149. ????????}??
150. ??
151. ????????return?new?String(encodedData);??
152. ????}??
153. ??
154. ????/**?
155. ?????*?Decodes?Base64?data?into?octects?
156. ?????*?
157. ?????*?@param?encoded?string?containing?Base64?data?
158. ?????*?@return?Array?containind?decoded?data.?
159. ?????*/??
160. ????public?static?byte[]?decode(String?encoded)?{??
161. ??
162. ????????if?(encoded?==?null)?{??
163. ????????????return?null;??
164. ????????}??
165. ??
166. ????????char[]?base64Data?=?encoded.toCharArray();??
167. ????????//?remove?white?spaces??
168. ????????int?len?=?removeWhiteSpace(base64Data);??
169. ??
170. ????????if?(len?%?FOURBYTE?!=?0)?{??
171. ????????????return?null;//should?be?divisible?by?four??
172. ????????}??
173. ??
174. ????????int?numberQuadruple?=?(len?/?FOURBYTE);??
175. ??
176. ????????if?(numberQuadruple?==?0)?{??
177. ????????????return?new?byte[0];??
178. ????????}??
179. ??
180. ????????byte?decodedData[]?=?null;??
181. ????????byte?b1?=?0,?b2?=?0,?b3?=?0,?b4?=?0;??
182. ????????char?d1?=?0,?d2?=?0,?d3?=?0,?d4?=?0;??
183. ??
184. ????????int?i?=?0;??
185. ????????int?encodedIndex?=?0;??
186. ????????int?dataIndex?=?0;??
187. ????????decodedData?=?new?byte[(numberQuadruple)?*?3];??
188. ??
189. ????????for?(;?i?<?numberQuadruple?-?1;?i++)?{??
190. ??
191. ????????????if?(!isData((d1?=?base64Data[dataIndex++]))?||?!isData((d2?=?base64Data[dataIndex++]))??
192. ????????????????||?!isData((d3?=?base64Data[dataIndex++]))??
193. ????????????????||?!isData((d4?=?base64Data[dataIndex++])))?{??
194. ????????????????return?null;??
195. ????????????}//if?found?"no?data"?just?return?null??
196. ??
197. ????????????b1?=?base64Alphabet[d1];??
198. ????????????b2?=?base64Alphabet[d2];??
199. ????????????b3?=?base64Alphabet[d3];??
200. ????????????b4?=?base64Alphabet[d4];??
201. ??
202. ????????????decodedData[encodedIndex++]?=?(byte)?(b1?<<?2?|?b2?>>?4);??
203. ????????????decodedData[encodedIndex++]?=?(byte)?(((b2?&?0xf)?<<?4)?|?((b3?>>?2)?&?0xf));??
204. ????????????decodedData[encodedIndex++]?=?(byte)?(b3?<<?6?|?b4);??
205. ????????}??
206. ??
207. ????????if?(!isData((d1?=?base64Data[dataIndex++]))?||?!isData((d2?=?base64Data[dataIndex++])))?{??
208. ????????????return?null;//if?found?"no?data"?just?return?null??
209. ????????}??
210. ??
211. ????????b1?=?base64Alphabet[d1];??
212. ????????b2?=?base64Alphabet[d2];??
213. ??
214. ????????d3?=?base64Data[dataIndex++];??
215. ????????d4?=?base64Data[dataIndex++];??
216. ????????if?(!isData((d3))?||?!isData((d4)))?{//Check?if?they?are?PAD?characters??
217. ????????????if?(isPad(d3)?&&?isPad(d4))?{??
218. ????????????????if?((b2?&?0xf)?!=?0)//last?4?bits?should?be?zero??
219. ????????????????{??
220. ????????????????????return?null;??
221. ????????????????}??
222. ????????????????byte[]?tmp?=?new?byte[i?*?3?+?1];??
223. ????????????????System.arraycopy(decodedData,?0,?tmp,?0,?i?*?3);??
224. ????????????????tmp[encodedIndex]?=?(byte)?(b1?<<?2?|?b2?>>?4);??
225. ????????????????return?tmp;??
226. ????????????}?else?if?(!isPad(d3)?&&?isPad(d4))?{??
227. ????????????????b3?=?base64Alphabet[d3];??
228. ????????????????if?((b3?&?0x3)?!=?0)//last?2?bits?should?be?zero??
229. ????????????????{??
230. ????????????????????return?null;??
231. ????????????????}??
232. ????????????????byte[]?tmp?=?new?byte[i?*?3?+?2];??
233. ????????????????System.arraycopy(decodedData,?0,?tmp,?0,?i?*?3);??
234. ????????????????tmp[encodedIndex++]?=?(byte)?(b1?<<?2?|?b2?>>?4);??
235. ????????????????tmp[encodedIndex]?=?(byte)?(((b2?&?0xf)?<<?4)?|?((b3?>>?2)?&?0xf));??
236. ????????????????return?tmp;??
237. ????????????}?else?{??
238. ????????????????return?null;??
239. ????????????}??
240. ????????}?else?{?//No?PAD?e.g?3cQl??
241. ????????????b3?=?base64Alphabet[d3];??
242. ????????????b4?=?base64Alphabet[d4];??
243. ????????????decodedData[encodedIndex++]?=?(byte)?(b1?<<?2?|?b2?>>?4);??
244. ????????????decodedData[encodedIndex++]?=?(byte)?(((b2?&?0xf)?<<?4)?|?((b3?>>?2)?&?0xf));??
245. ????????????decodedData[encodedIndex++]?=?(byte)?(b3?<<?6?|?b4);??
246. ??
247. ????????}??
248. ??
249. ????????return?decodedData;??
250. ????}??
251. ??
252. ????/**?
253. ?????*?remove?WhiteSpace?from?MIME?containing?encoded?Base64?data.?
254. ?????*?
255. ?????*?@param?data??the?byte?array?of?base64?data?(with?WS)?
256. ?????*?@return??????the?new?length?
257. ?????*/??
258. ????private?static?int?removeWhiteSpace(char[]?data)?{??
259. ????????if?(data?==?null)?{??
260. ????????????return?0;??
261. ????????}??
262. ??
263. ????????//?count?characters?that's?not?whitespace??
264. ????????int?newSize?=?0;??
265. ????????int?len?=?data.length;??
266. ????????for?(int?i?=?0;?i?<?len;?i++)?{??
267. ????????????if?(!isWhiteSpace(data[i]))?{??
268. ????????????????data[newSize++]?=?data[i];??
269. ????????????}??
270. ????????}??
271. ????????return?newSize;??
272. ????}??
273. }??

?

最后是一个MainTest：

?

1. package?com.ihep;??
2. ??
3. public?class?MainTest?{??
4. ??
5. ????public?static?void?main(String[]?args)?throws?Exception?{??
6. ????????String?filepath="G:/tmp/";??
7. ??
8. ????????//RSAEncrypt.genKeyPair(filepath);??
9. ??????????
10. ??????????
11. ????????System.out.println("--------------公钥加密私钥解密过程-------------------");??
12. ????????String?plainText="ihep_公钥加密私钥解密";??
13. ????????//公钥加密过程??
14. ????????byte[]?cipherData=RSAEncrypt.encrypt(RSAEncrypt.loadPublicKeyByStr(RSAEncrypt.loadPublicKeyByFile(filepath)),plainText.getBytes());??
15. ????????String?cipher=Base64.encode(cipherData);??
16. ????????//私钥解密过程??
17. ????????byte[]?res=RSAEncrypt.decrypt(RSAEncrypt.loadPrivateKeyByStr(RSAEncrypt.loadPrivateKeyByFile(filepath)),?Base64.decode(cipher));??
18. ????????String?restr=new?String(res);??
19. ????????System.out.println("原文："+plainText);??
20. ????????System.out.println("加密："+cipher);??
21. ????????System.out.println("解密："+restr);??
22. ????????System.out.println();??
23. ??????????
24. ????????System.out.println("--------------私钥加密公钥解密过程-------------------");??
25. ????????plainText="ihep_私钥加密公钥解密";??
26. ????????//私钥加密过程??
27. ????????cipherData=RSAEncrypt.encrypt(RSAEncrypt.loadPrivateKeyByStr(RSAEncrypt.loadPrivateKeyByFile(filepath)),plainText.getBytes());??
28. ????????cipher=Base64.encode(cipherData);??
29. ????????//公钥解密过程??
30. ????????res=RSAEncrypt.decrypt(RSAEncrypt.loadPublicKeyByStr(RSAEncrypt.loadPublicKeyByFile(filepath)),?Base64.decode(cipher));??
31. ????????restr=new?String(res);??
32. ????????System.out.println("原文："+plainText);??
33. ????????System.out.println("加密："+cipher);??
34. ????????System.out.println("解密："+restr);??
35. ????????System.out.println();??
36. ??????????
37. ????????System.out.println("---------------私钥签名过程------------------");??
38. ????????String?content="ihep_这是用于签名的原始数据";??
39. ????????String?signstr=RSASignature.sign(content,RSAEncrypt.loadPrivateKeyByFile(filepath));??
40. ????????System.out.println("签名原串："+content);??
41. ????????System.out.println("签名串："+signstr);??
42. ????????System.out.println();??
43. ??????????
44. ????????System.out.println("---------------公钥校验签名------------------");??
45. ????????System.out.println("签名原串："+content);??
46. ????????System.out.println("签名串："+signstr);??
47. ??????????
48. ????????System.out.println("验签结果："+RSASignature.doCheck(content,?signstr,?RSAEncrypt.loadPublicKeyByFile(filepath)));??
49. ????????System.out.println();??
50. ??????????
51. ????}??
52. }??

?

看看运行截图：

?