| 提交 | 用户 | 时间 | ||
| 1ac2bc | 1 | package cn.stylefeng.guns.workflow.core.util; |
| 懒 | 2 | |
| 3 | import java.io.*; | |
| 4 | import java.nio.ByteBuffer; | |
| 5 | import java.nio.MappedByteBuffer; | |
| 6 | import java.nio.channels.FileChannel; | |
| 7 | import java.nio.channels.FileChannel.MapMode; | |
| 8 | ||
| 9 | /** | |
| 10 | * 文件处理 | |
| 11 | * | |
| 12 | * @author fengshuonan | |
| 13 | * @Date 2019/8/7 23:14 | |
| 14 | */ | |
| 15 | public class FileUtil { | |
| 16 | ||
| 17 | ||
| 18 | /** | |
| 19 | * 获取文件大小 返回 KB 保留3位小数 没有文件时返回0 | |
| 20 | * | |
| 21 | * @param filepath 文件完整路径，包括文件名 | |
| 22 | * @return | |
| 23 | */ | |
| 24 | public static Double getFilesize(String filepath) { | |
| 25 | File backupath = new File(filepath); | |
| 26 | return Double.valueOf(backupath.length()) / 1000.000; | |
| 27 | } | |
| 28 | ||
| 29 | /** | |
| 30 | * 创建目录 | |
| 31 | * | |
| 32 | * @param destDirName目标目录名 | |
| 33 | * @return | |
| 34 | */ | |
| 35 | public static Boolean createDir(String destDirName) { | |
| 36 | File dir = new File(destDirName); | |
| 37 | if (!dir.getParentFile().exists()) { //判断有没有父路径，就是判断文件整个路径是否存在 | |
| 38 | return dir.getParentFile().mkdirs(); //不存在就全部创建 | |
| 39 | } | |
| 40 | return false; | |
| 41 | } | |
| 42 | ||
| 43 | /** | |
| 44 | * 删除文件 | |
| 45 | * | |
| 46 | * @param filePathAndName String 文件路径及名称 如c:/fqf.txt | |
| 47 | * @param fileContent String | |
| 48 | * @return boolean | |
| 49 | */ | |
| 50 | public static void delFile(String filePathAndName) { | |
| 51 | try { | |
| 52 | String filePath = filePathAndName; | |
| 53 | filePath = filePath.toString(); | |
| 54 | java.io.File myDelFile = new java.io.File(filePath); | |
| 55 | myDelFile.delete(); | |
| 56 | } catch (Exception e) { | |
| 57 | System.out.println("删除文件操作出错"); | |
| 58 | e.printStackTrace(); | |
| 59 | } | |
| 60 | } | |
| 61 | ||
| 62 | /** | |
| 63 | * 读取到字节数组0 | |
| 64 | * | |
| 65 | * @param filePath //路径 | |
| 66 | * @throws IOException | |
| 67 | */ | |
| 68 | public static byte[] getContent(String filePath) throws IOException { | |
| 69 | File file = new File(filePath); | |
| 70 | long fileSize = file.length(); | |
| 71 | if (fileSize > Integer.MAX_VALUE) { | |
| 72 | System.out.println("file too big..."); | |
| 73 | return null; | |
| 74 | } | |
| 75 | FileInputStream fi = new FileInputStream(file); | |
| 76 | byte[] buffer = new byte[(int) fileSize]; | |
| 77 | int offset = 0; | |
| 78 | int numRead = 0; | |
| 79 | while (offset < buffer.length | |
| 80 | && (numRead = fi.read(buffer, offset, buffer.length - offset)) >= 0) { | |
| 81 | offset += numRead; | |
| 82 | } | |
| 83 | // 确保所有数据均被读取 | |
| 84 | if (offset != buffer.length) { | |
| 85 | throw new IOException("Could not completely read file " + file.getName()); | |
| 86 | } | |
| 87 | fi.close(); | |
| 88 | return buffer; | |
| 89 | } | |
| 90 | ||
| 91 | /** | |
| 92 | * 读取到字节数组1 | |
| 93 | * | |
| 94 | * @param filePath | |
| 95 | * @return | |
| 96 | * @throws IOException | |
| 97 | */ | |
| 98 | public static byte[] toByteArray(String filePath) throws IOException { | |
| 99 | ||
| 100 | File f = new File(filePath); | |
| 101 | if (!f.exists()) { | |
| 102 | throw new FileNotFoundException(filePath); | |
| 103 | } | |
| 104 | ByteArrayOutputStream bos = new ByteArrayOutputStream((int) f.length()); | |
| 105 | BufferedInputStream in = null; | |
| 106 | try { | |
| 107 | in = new BufferedInputStream(new FileInputStream(f)); | |
| 108 | int buf_size = 1024; | |
| 109 | byte[] buffer = new byte[buf_size]; | |
| 110 | int len = 0; | |
| 111 | while (-1 != (len = in.read(buffer, 0, buf_size))) { | |
| 112 | bos.write(buffer, 0, len); | |
| 113 | } | |
| 114 | return bos.toByteArray(); | |
| 115 | } catch (IOException e) { | |
| 116 | e.printStackTrace(); | |
| 117 | throw e; | |
| 118 | } finally { | |
| 119 | try { | |
| 120 | in.close(); | |
| 121 | } catch (IOException e) { | |
| 122 | e.printStackTrace(); | |
| 123 | } | |
| 124 | bos.close(); | |
| 125 | } | |
| 126 | } | |
| 127 | ||
| 128 | /** | |
| 129 | * 读取到字节数组2 | |
| 130 | * | |
| 131 | * @param filePath | |
| 132 | * @return | |
| 133 | * @throws IOException | |
| 134 | */ | |
| 135 | public static byte[] toByteArray2(String filePath) throws IOException { | |
| 136 | File f = new File(filePath); | |
| 137 | if (!f.exists()) { | |
| 138 | throw new FileNotFoundException(filePath); | |
| 139 | } | |
| 140 | FileChannel channel = null; | |
| 141 | FileInputStream fs = null; | |
| 142 | try { | |
| 143 | fs = new FileInputStream(f); | |
| 144 | channel = fs.getChannel(); | |
| 145 | ByteBuffer byteBuffer = ByteBuffer.allocate((int) channel.size()); | |
| 146 | while ((channel.read(byteBuffer)) > 0) { | |
| 147 | // do nothing | |
| 148 | // System.out.println("reading"); | |
| 149 | } | |
| 150 | return byteBuffer.array(); | |
| 151 | } catch (IOException e) { | |
| 152 | e.printStackTrace(); | |
| 153 | throw e; | |
| 154 | } finally { | |
| 155 | try { | |
| 156 | channel.close(); | |
| 157 | } catch (IOException e) { | |
| 158 | e.printStackTrace(); | |
| 159 | } | |
| 160 | try { | |
| 161 | fs.close(); | |
| 162 | } catch (IOException e) { | |
| 163 | e.printStackTrace(); | |
| 164 | } | |
| 165 | } | |
| 166 | } | |
| 167 | ||
| 168 | /** | |
| 169 | * Mapped File way MappedByteBuffer 可以在处理大文件时，提升性能 | |
| 170 | * | |
| 171 | * @param filename | |
| 172 | * @return | |
| 173 | * @throws IOException | |
| 174 | */ | |
| 175 | public static byte[] toByteArray3(String filePath) throws IOException { | |
| 176 | ||
| 177 | FileChannel fc = null; | |
| 178 | RandomAccessFile rf = null; | |
| 179 | try { | |
| 180 | rf = new RandomAccessFile(filePath, "r"); | |
| 181 | fc = rf.getChannel(); | |
| 182 | MappedByteBuffer byteBuffer = fc.map(MapMode.READ_ONLY, 0, | |
| 183 | fc.size()).load(); | |
| 184 | //System.out.println(byteBuffer.isLoaded()); | |
| 185 | byte[] result = new byte[(int) fc.size()]; | |
| 186 | if (byteBuffer.remaining() > 0) { | |
| 187 | // System.out.println("remain"); | |
| 188 | byteBuffer.get(result, 0, byteBuffer.remaining()); | |
| 189 | } | |
| 190 | return result; | |
| 191 | } catch (IOException e) { | |
| 192 | e.printStackTrace(); | |
| 193 | throw e; | |
| 194 | } finally { | |
| 195 | try { | |
| 196 | rf.close(); | |
| 197 | fc.close(); | |
| 198 | } catch (IOException e) { | |
| 199 | e.printStackTrace(); | |
| 200 | } | |
| 201 | } | |
| 202 | } | |
| 203 | ||
| 204 | } | |
