Java文件操作大全
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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 //提取扩展名
473 String str2=str1.substring(str1.lastIndexOf(".")+1);
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