
平台论坛博客文库

› 论坛 › 程序设计 › Java › Java文件操作大全

Java文件操作大全 [复制链接]

听老歌

家境小康

论坛徽章:: 0

电梯直达

1楼 [收藏(0)] [报告]

发表于 2011-05-17 13:22 |只看该作者 |倒序浏览

Java文件操作大全

Java代码

1.//1.创建文件夹
2.//import java.io.*;
3.File myFolderPath = new File(str1);
4.try {
5. if (!myFolderPath.exists()) {
6. myFolderPath.mkdir();
7. }
8.}
9.catch (Exception e) {
10. System.out.println("新建目录操作出错");
11. e.printStackTrace();
12.}
13.
14.//2.创建文件
15.//import java.io.*;
16.File myFilePath = new File(str1);
17.try {
18. if (!myFilePath.exists()) {
19. myFilePath.createNewFile();
20. }
21. FileWriter resultFile = new FileWriter(myFilePath);
22. PrintWriter myFile = new PrintWriter(resultFile);
23. myFile.println(str2);
24. resultFile.close();
25.}
26.catch (Exception e) {
27. System.out.println("新建文件操作出错");
28. e.printStackTrace();
29.}
30.
31.//3.删除文件
32.//import java.io.*;
33.File myDelFile = new File(str1);
34.try {
35. myDelFile.delete();
36.}
37.catch (Exception e) {
38. System.out.println("删除文件操作出错");
39. e.printStackTrace();
40.}
41.
42.//4.删除文件夹
43.//import java.io.*;
44.File delFolderPath = new File(str1);
45.try {
46. delFolderPath.delete(); //删除空文件夹
47.}
48.catch (Exception e) {
49. System.out.println("删除文件夹操作出错");
50. e.printStackTrace();
51.}
52.
53.//5.删除一个文件下夹所有的文件夹
54.//import java.io.*;
55.File delfile=new File(str1);
56.File[] files=delfile.listFiles();
57.for(int i=0;i<files.length;i++){
58. if(files[i].isDirectory()){
59. files[i].delete();
60. }
61.}
62.
63.//6.清空文件夹
64.//import java.io.*;
65.File delfilefolder=new File(str1);
66.try {
67. if (!delfilefolder.exists()) {
68. delfilefolder.delete();
69. }
70. delfilefolder.mkdir();
71.}
72.catch (Exception e) {
73. System.out.println("清空目录操作出错");
74. e.printStackTrace();
75.}
76.
77.//7.读取文件
78.//import java.io.*;
79.// 逐行读取数据
80.FileReader fr = new FileReader(str1);
81.BufferedReader br = new BufferedReader(fr);
82.String str2 = br.readLine();
83.while (str2 != null) {
84. str3
85. str2 = br.readLine();
86.}
87.br.close();
88.fr.close();
89.
90.//8.写入文件
91.//import java.io.*;
92.// 将数据写入文件
93.try {
94. FileWriter fw = new FileWriter(str1);
95. fw.write(str2);
96. fw.flush();
97. fw.close();
98.} catch (IOException e) {
99. e.printStackTrace();
100.}
101.
102.//9.写入随机文件
103.//import java.io.*;
104.try {
105. RandomAcessFile logFile=new RandomAcessFile(str1,"rw");
106. long lg=logFile.length();
107. logFile.seek(str2);
108. logFile.writeByte(str3);
109.}catch(IOException ioe){
110. System.out.println("无法写入文件："+ioe.getMessage());
111.}
112.
113.//10.读取文件属性
114.//import java.io.*;
115.// 文件属性的取得
116.File f = new File(str1);
117.if (af.exists()) {
118. System.out.println(f.getName() + "的属性如下：文件长度为：" + f.length());
119. System.out.println(f.isFile() ? "是文件" : "不是文件");
120. System.out.println(f.isDirectory() ? "是目录" : "不是目录");
121. System.out.println(f.canRead() ? "可读取" : "不");
122. System.out.println(f.canWrite() ? "是隐藏文件" : "");
123. System.out.println("文件夹的最后修改日期为：" + new Date(f.lastModified()));
124. } else {
125. System.out.println(f.getName() + "的属性如下：");
126. System.out.println(f.isFile() ? "是文件" : "不是文件");
127. System.out.println(f.isDirectory() ? "是目录" : "不是目录");
128. System.out.println(f.canRead() ? "可读取" : "不");
129. System.out.println(f.canWrite() ? "是隐藏文件" : "");
130. System.out.println("文件的最后修改日期为：" + new Date(f.lastModified()));
131.}
132.if(f.canRead()){
133. str2
134.}
135.if(f.canWrite()){
136. str3
137.}
138.
139.//11.写入属性
140.//import java.io.*;
141.File filereadonly=new File(str1);
142.try {
143. boolean b=filereadonly.setReadOnly();
144.}
145.catch (Exception e) {
146. System.out.println("拒绝写访问："+e.printStackTrace());
147.}
148.
149.//12.枚举一个文件夹中的所有文件
150.//import java.io.*;
151.//import java.util.*;
152.LinkedList<String> folderList = new LinkedList<String>();
153.folderList.add(str1);
154.while (folderList.size() > 0) {
155. File file = new File(folderList.peek());
156. folderList.removeLast();
157. File[] files = file.listFiles();
158. ArrayList<File> fileList = new ArrayList<File>();
159. for (int i = 0; i < files.length; i++) {
160. if (files[i].isDirectory()) {
161. folderList.add(files[i].getPath());
162. } else {
163. fileList.add(files[i]);
164. }
165. }
166. for (File f : fileList) {
167. str2=f.getAbsoluteFile();
168. str3
169. }
170.}
171.
172.//13.复制文件夹
173.//import java.io.*;
174.//import java.util.*;
175.LinkedList<String> folderList = new LinkedList<String>();
176.folderList.add(str1);
177.LinkedList<String> folderList2 = new LinkedList<String>();
178.folderList2.add(str2+ str1.substring(str1.lastIndexOf("\\")));
179.while (folderList.size() > 0) {
180. (new File(folderList2.peek())).mkdirs(); // 如果文件夹不存在则建立新文件夹
181. File folders = new File(folderList.peek());
182. String[] file = folders.list();
183. File temp = null;
184. try {
185. for (int i = 0; i < file.length; i++) {
186. if (folderList.peek().endsWith(File.separator)) {
187. temp = new File(folderList.peek() + File.separator
188. + file[i]);
189. } else {
190. temp = new File(folderList.peek() + File.separator + file[i]);
191. }
192. if (temp.isFile()) {
193. FileInputStream input = new FileInputStream(temp);
194. FileOutputStream output = new FileOutputStream(
195. folderList2.peek() + File.separator + (temp.getName()).toString());
196. byte[] b = new byte[5120];
197. int len;
198. while ((len = input.read(b)) != -1) {
199. output.write(b, 0, len);
200. }
201. output.flush();
202. output.close();
203. input.close();
204. }
205. if (temp.isDirectory()) {// 如果是子文件夹
206. for (File f : temp.listFiles()) {
207. if (f.isDirectory()) {
208. folderList.add(f.getPath());
209. folderList2.add(folderList2.peek()
210. + File.separator + f.getName());
211. }
212. }
213. }
214. }
215. } catch (Exception e) {
216. //System.out.println("复制整个文件夹内容操作出错");
217. e.printStackTrace();
218. }
219. folderList.removeFirst();
220. folderList2.removeFirst();
221.}
222.
223.//14.复制一个文件夹下所有的文件夹到另一个文件夹下
224.//import java.io.*;
225.//import java.util.*;
226.File copyfolders=new File(str1);
227.File[] copyfoldersList=copyfolders.listFiles();
228.for(int k=0;k<copyfoldersList.length;k++){
229. if(copyfoldersList[k].isDirectory()){
230. ArrayList<String>folderList=new ArrayList<String>();
231. folderList.add(copyfoldersList[k].getPath());
232. ArrayList<String>folderList2=new ArrayList<String>();
233. folderList2.add(str2+"/"+copyfoldersList[k].getName());
234. for(int j=0;j<folderList.length;j++){
235. (new File(folderList2.get(j))).mkdirs(); //如果文件夹不存在则建立新文件夹
236. File folders=new File(folderList.get(j));
237. String[] file=folders.list();
238. File temp=null;
239. try {
240. for (int i = 0; i < file.length; i++) {
241. if(folderList.get(j).endsWith(File.separator)){
242. temp=new File(folderList.get(j)+"/"+file[i]);
243. } else {
244. temp=new File(folderList.get(j)+"/"+File.separator+file[i]);
245. }
246. FileInputStream input = new FileInputStream(temp);
247. if(temp.isFile()){
248. FileInputStream input = new FileInputStream(temp);
249. FileOutputStream output = new FileOutputStream(folderList2.get(j) + "/" + (temp.getName()).toString());
250. byte[] b = new byte[5120];
251. int len;
252. while ( (len = input.read(b)) != -1) {
253. output.write(b, 0, len);
254. }
255. output.flush();
256. output.close();
257. input.close();
258. }
259. if(temp.isDirectory()){//如果是子文件夹
260. folderList.add(folderList.get(j)+"/"+file[i]);
261. folderList2.add(folderList2.get(j)+"/"+file[i]);
262. }
263. }
264. }
265. catch (Exception e) {
266. System.out.println("复制整个文件夹内容操作出错");
267. e.printStackTrace();
268. }
269. }
270. }
271.}
272.
273.//15.移动文件夹
274.//import java.io.*;
275.//import java.util.*;
276.LinkedList<String> folderList = new LinkedList<String>();
277.folderList.add(str1);
278.LinkedList<String> folderList2 = new LinkedList<String>();
279.folderList2.add(str2 + str1.substring(str1.lastIndexOf("\\")));
280.while (folderList.size() > 0) {
281. (new File(folderList2.peek())).mkdirs(); // 如果文件夹不存在则建立新文件夹
282. File folders = new File(folderList.peek());
283. String[] file = folders.list();
284. File temp = null;
285. try {
286. for (int i = 0; i < file.length; i++) {
287. if (folderList.peek().endsWith(File.separator)) {
288. temp = new File(folderList.peek() + File.separator + file[i]);
289. } else {
290. temp = new File(folderList.peek() + File.separator + file[i]);
291. }
292. if (temp.isFile()) {
293. FileInputStream input = new FileInputStream(temp);
294. FileOutputStream output = new FileOutputStream(
295. folderList2.peek() + File.separator + (temp.getName()).toString());
296. byte[] b = new byte[5120];
297. int len;
298. while ((len = input.read(b)) != -1) {
299. output.write(b, 0, len);
300. }
301. output.flush();
302. output.close();
303. input.close();
304. if (!temp.delete())
305. System.out.println("删除单个文件操作出错!");
306. }
307. if (temp.isDirectory()) {// 如果是子文件夹
308. for (File f : temp.listFiles()) {
309. if (f.isDirectory()) {
310. folderList.add(f.getPath());
311. folderList2.add(folderList2.peek() + File.separator + f.getName());
312. }
313. }
314. }
315. }
316. } catch (Exception e) {
317. // System.out.println("复制整个文件夹内容操作出错");
318. e.printStackTrace();
319. }
320. folderList.removeFirst();
321. folderList2.removeFirst();
322.}
323.File f = new File(str1);
324.if (!f.delete()) {
325. for (File file : f.listFiles()) {
326. if (file.list().length == 0) {
327. System.out.println(file.getPath());
328. file.delete();
329. }
330. }
331.}
332.//16.移动一个文件夹下所有的文件夹到另一个目录下
333.//import java.io.*;
334.//import java.util.*;
335.File movefolders=new File(str1);
336.File[] movefoldersList=movefolders.listFiles();
337.for(int k=0;k<movefoldersList.length;k++){
338. if(movefoldersList[k].isDirectory()){
339. ArrayList<String>folderList=new ArrayList<String>();
340. folderList.add(movefoldersList[k].getPath());
341. ArrayList<String>folderList2=new ArrayList<String>();
342. folderList2.add(str2+"/"+movefoldersList[k].getName());
343. for(int j=0;j<folderList.length;j++){
344. (new File(folderList2.get(j))).mkdirs(); //如果文件夹不存在则建立新文件夹
345. File folders=new File(folderList.get(j));
346. String[] file=folders.list();
347. File temp=null;
348. try {
349. for (int i = 0; i < file.length; i++) {
350. if(folderList.get(j).endsWith(File.separator)){
351. temp=new File(folderList.get(j)+"/"+file[i]);
352. }
353. else{
354. temp=new File(folderList.get(j)+"/"+File.separator+file[i]);
355. }
356. FileInputStream input = new FileInputStream(temp);
357. if(temp.isFile()){
358. FileInputStream input = new FileInputStream(temp);
359. FileOutputStream output = new FileOutputStream(folderList2.get(j) + "/" + (temp.getName()).toString());
360. byte[] b = new byte[5120];
361. int len;
362. while ( (len = input.read(b)) != -1) {
363. output.write(b, 0, len);
364. }
365. output.flush();
366. output.close();
367. input.close();
368. temp.delete();
369. }
370. if(temp.isDirectory()){//如果是子文件夹
371. folderList.add(folderList.get(j)+"/"+file[i]);
372. folderList2.add(folderList2.get(j)+"/"+file[i]);
373. }
374. }
375. }
376. catch (Exception e) {
377. System.out.println("复制整个文件夹内容操作出错");
378. e.printStackTrace();
379. }
380. }
381. movefoldersList[k].delete();
382. }
383.}
384.
385.//17.以一个文件夹的框架在另一个目录创建文件夹和空文件
386.//import java.io.*;
387.//import java.util.*;
388.boolean b=false;//不创建空文件
389.ArrayList<String>folderList=new ArrayList<String>();
390.folderList.add(str1);
391.ArrayList<String>folderList2=new ArrayList<String>();
392.folderList2.add(str2);
393.for(int j=0;j<folderList.length;j++){
394. (new File(folderList2.get(j))).mkdirs(); //如果文件夹不存在则建立新文件夹
395. File folders=new File(folderList.get(j));
396. String[] file=folders.list();
397. File temp=null;
398. try {
399. for (int i = 0; i < file.length; i++) {
400. if(folderList.get(j).endsWith(File.separator)){
401. temp=new File(folderList.get(j)+"/"+file[i]);
402. }
403. else{
404. temp=new File(folderList.get(j)+"/"+File.separator+file[i]);
405. }
406. FileInputStream input = new FileInputStream(temp);
407. if(temp.isFile()){
408. if (b) temp.createNewFile();
409. }
410. if(temp.isDirectory()){//如果是子文件夹
411. folderList.add(folderList.get(j)+"/"+file[i]);
412. folderList2.add(folderList2.get(j)+"/"+file[i]);
413. }
414. }
415. }
416. catch (Exception e) {
417. System.out.println("复制整个文件夹内容操作出错");
418. e.printStackTrace();
419. }
420.}
421.
422.//18.复制文件
423.//import java.io.*;
424. int bytesum = 0;
425. int byteread = 0;
426. File oldfile = new File(str1);
427. try {
428. if (oldfile.exists()) { //文件存在时
429. FileInputStream inStream = new FileInputStream(oldfile); //读入原文件
430. FileOutputStream fs = new FileOutputStream(new File(str2,oldfile.getName()));
431. byte[] buffer = new byte[5120];
432. int length;
433. while ( (byteread = inStream.read(buffer)) != -1) {
434. bytesum += byteread; //字节数文件大小
435. System.out.println(bytesum);
436. fs.write(buffer, 0, byteread);
437. }
438. inStream.close();
439. }
440. }
441. catch (Exception e) {
442. System.out.println("复制单个文件操作出错");
443. e.printStackTrace();
444. }
445.
446.//19.复制一个文件夹下所有的文件到另一个目录
447.//import java.io.*;
448.File copyfiles=new File(str1);
449.File[] files=copyfiles.listFiles();
450.for(int i=0;i<files.length;i++){
451. if(!files[i].isDirectory()){
452. int bytesum = 0;
453. int byteread = 0;
454. try {
455. InputStream inStream = new FileInputStream(files[i]); //读入原文件
456. FileOutputStream fs = new FileOutputStream(new File(str2,files[i].getName());
457. byte[] buffer = new byte[5120];
458. int length;
459. while ( (byteread = inStream.read(buffer)) != -1) {
460. bytesum += byteread; //字节数文件大小
461. System.out.println(bytesum);
462. fs.write(buffer, 0, byteread);
463. }
464. inStream.close();
465. } catch (Exception e) {
466. System.out.println("复制单个文件操作出错");
467. e.printStackTrace();
468. }
469. }
470.}
471.
472.//20.提取扩展名
473.String str2=str1.substring(str1.lastIndexOf(".")+1);