JAVA 文件操作
java IO最基本操作总结~~~
1 文件写入
2 读取文件内容
3 删除文件
4 复制文件内容到另一文件
5 向文件中追加数据
6 创建临时文件
7 修改文件最后修改日期
8 获取文件大小
9 文件重命名
10 设置文件为只读模式
11 检测文件是否存在
12 在指定目录创建文件
13 获取文件需改时间
14 创建文件
15 文件路径比较
1 import java.io.*; 2 import java.util.*; 3 4 public class FileControl { 5 public static void main(String[] args) throws Exception{ 6 FileWrite(); 7 FileRead(); 8 FileDel(); 9 FileCopy(); 10 FileAddData(); 11 FileCreatTemporary(); 12 FileLastDate(); 13 FileGetSize(); 14 FileRename(); 15 FileOnlyRead(); 16 FileIfExist(); 17 FileCreatFile(); 18 FileGetChangeDate(); 19 FileCreat(); 20 FilePathCompare(); 21 } 22 23 // 文件写入 24 private static void FileWrite(){ 25 try { 26 BufferedWriter out = new BufferedWriter(new FileWriter("outfilename")); 27 out.write("w3cSchool"); 28 out.close(); 29 System.out.println("文件创建成功!"); 30 }catch (IOException e){ 31 e.printStackTrace(); 32 } 33 } 34 // 读取文件内容 35 private static void FileRead(){ 36 try { 37 BufferedReader in = new BufferedReader(new FileReader("test.log")); 38 String str; 39 while ((str = in.readLine()) != null){ 40 System.out.println(str); 41 } 42 }catch (IOException e){ 43 e.printStackTrace(); 44 } 45 } 46 // 删除文件 47 private static void FileDel(){ 48 try { 49 File file = new File("text.txt"); 50 if (file.delete()){ 51 System.out.println(file.getName() + "文件已被删除!"); 52 }else { 53 System.out.println("文件删除失败!"); 54 } 55 }catch (Exception e){ 56 e.printStackTrace(); 57 } 58 } 59 // 将文件内容复制到另一个文件 60 private static void FileCopy() throws Exception{ 61 BufferedWriter out1 = new BufferedWriter(new FileWriter("srcFile")); 62 out1.write("String to be copied\n"); 63 out1.close(); 64 InputStream in = new FileInputStream(new File("srcFile")); 65 OutputStream out = new FileOutputStream(new File("destnfile")); 66 byte[] buf = new byte[1024]; 67 int len; 68 while ((len = in.read(buf)) > 0){ 69 out.write(buf, 0, len); 70 } 71 in.close(); 72 out1.close(); 73 BufferedReader in1 = new BufferedReader(new FileReader("destnfile")); 74 String str; 75 while ((str = in1.readLine()) != null){ 76 System.out.println(str); 77 } 78 in1.close(); 79 } 80 // 向文件中追加数据 81 private static void FileAddData(){ 82 try { 83 BufferedWriter out = new BufferedWriter(new FileWriter("filename")); 84 out.write("aString1\n"); 85 out.close(); 86 out = new BufferedWriter(new FileWriter("filename", true)); 87 out.write("aString2"); 88 out.close(); 89 BufferedReader in = new BufferedReader(new FileReader("filename")); 90 String str; 91 while ((str = in.readLine()) != null){ 92 System.out.println(str); 93 } 94 in.close(); 95 }catch (IOException e){ 96 System.out.println("Exception occoured" + e); 97 } 98 } 99 // 创建临时文件 100 private static void FileCreatTemporary() throws Exception{ 101 File temp = File.createTempFile("pattern", ".suffix"); 102 temp.deleteOnExit(); 103 BufferedWriter out = new BufferedWriter(new FileWriter(temp)); 104 out.write("aString"); 105 System.out.println("临时文件已创建"); 106 out.close(); 107 } 108 // 修改文件最后日期 109 private static void FileLastDate() throws Exception{ 110 File fileToChange = new File("myJava.txt"); 111 fileToChange.createNewFile(); 112 Date filetime = new Date(fileToChange.lastModified()); 113 System.out.println(filetime.toString()); 114 System.out.println(fileToChange.setLastModified(System.currentTimeMillis())); 115 filetime = new Date(fileToChange.lastModified()); 116 System.out.println(filetime.toString()); 117 } 118 // 获取文件大小 119 public static long getFileSize(String filename){ 120 File file = new File(filename); 121 if (!file.exists() || !file.isFile()){ 122 System.out.println("文件不存在"); 123 return -1; 124 } 125 return file.length(); 126 } 127 private static void FileGetSize(){ 128 long size = getFileSize("java.txt"); 129 System.out.println("java文件的大小为:" + size); 130 } 131 // 文件重命名 132 private static void FileRename(){ 133 File oldName = new File("program.txt"); 134 File newName = new File("java.txt"); 135 if (oldName.renameTo(newName)){ 136 System.out.println("已经重命名"); 137 }else { 138 System.out.println("Error"); 139 } 140 } 141 // 设置文件只读模式 142 private static void FileOnlyRead(){ 143 File file = new File("java.txt"); 144 System.out.println(file.setReadOnly()); 145 System.out.println(file.canWrite()); 146 } 147 // 检测文件是否存在 148 private static void FileIfExist(){ 149 File file = new File("java.txt"); 150 System.out.println(file.exists()); 151 } 152 // 在指定文件中创建文件 153 private static void FileCreatFile() throws Exception{ 154 File file = null; 155 File dir = new File("E:/JAVA_CODE/"); 156 file = File.createTempFile("JavaTemp", ".javatemp", dir); 157 System.out.println(file.getPath()); 158 } 159 // 获取文件修改时间 160 private static void FileGetChangeDate(){ 161 File file = new File("MAIN.java"); 162 Long lastModified = file.lastModified(); 163 Date date = new Date(lastModified); 164 System.out.println(date); 165 } 166 // 创建文件 167 private static void FileCreat(){ 168 try { 169 File file = new File("E:/JAVA_CODE/myfile.txt"); 170 if (file.createNewFile()) 171 System.out.println("文件创建成功!"); 172 else System.out.println("创建文件出错!"); 173 }catch (IOException io){ 174 io.printStackTrace(); 175 } 176 } 177 // 文件路径比较 178 private static void FilePathCompare(){ 179 File file1 = new File("E:/demo1/demo.txt"); 180 File file2 = new File("E:/demo2/demo.txt"); 181 if (file1.compareTo(file2) == 0){ 182 System.out.println("文件路径一致!"); 183 }else { 184 System.out.println("文件路径不同!"); 185 } 186 } 187 }