53冗余备份java源码.docx

五三备份问题问题描述：任意一个文件，分割成5份，用其中任意3份均可恢复原文件。原创java源码，核心部分，外围扩展功能未实现。使用方法：请参见main函数。import java.io.*;import java.util.ArrayList;import java.lang.Long;public class RedundantBackup {private static final int MAX_SUB_FILE_COUNT = 5;private static final int BACKUP_SECTOR_COUNT = 3;private static final String SUB_EXT = .dmp;private String originalFile;public RedundantBackup(String OriginalFile) {this.originalFile = OriginalFile;}public void backup() {File f = new File(this.originalFile);if (f.exists()) {long FileLength = 0L;try {RandomAccessFile raf = new RandomAccessFile(new File(this.originalFile), r);FileLength = raf.length();raf.close();} catch (Exception e) {}long SubFileLength = FileLength / MAX_SUB_FILE_COUNT;long LastSectorLength = FileLength - SubFileLength * (MAX_SUB_FILE_COUNT - 1);ArrayListbyte[] data = new ArrayListbyte[]();try {FileInputStream fis = new FileInputStream(this.originalFile);for (int i = 0; i MAX_SUB_FILE_COUNT; i++) {if (i MAX_SUB_FILE_COUNT - 1) {byte[] b = new byte[(int) SubFileLength];fis.read(b, 0, (int) SubFileLength);data.add(b);} else {byte[] b = new byte[(int) LastSectorLength];fis.read(b, 0, (int) LastSectorLength);data.add(b);}}fis.close();} catch (IOException e) {e.printStackTrace();}RedundantFile[] rf = new RedundantFile[MAX_SUB_FILE_COUNT];for (int i = 0; i MAX_SUB_FILE_COUNT; i++) {rf[i] = new RedundantFile();rf[i].setFileFullName(this.originalFile + String.valueOf(i) + SUB_EXT);for (int j = 0; j BACKUP_SECTOR_COUNT; j++) {int k = i + j;k = (k MAX_SUB_FILE_COUNT) ? k : k % MAX_SUB_FILE_COUNT;rf[i].addSector(k, data.get(k));}rf[i].save(rf[i].getFileFullName());}data.clear();for (int i = 0; i MAX_SUB_FILE_COUNT; i++) {rf[i].dispose();}rf = null;}}public void merge(String BackupPath) {if ((new File(BackupPath)).exists()) {String[] rfFile = getFilesFromDirectory(BackupPath);if (rfFile != null rfFile.length = BACKUP_SECTOR_COUNT) {try {RedundantFile[] rf = new RedundantFile[BACKUP_SECTOR_COUNT];for (int i = 0; i BACKUP_SECTOR_COUNT;