background
要在很大的数据量中查询其中某些flag的值是否正常，debug看肯定不行，我就把flag都输出到log中，然后下班回家。回到家中发现log有2G多，编辑器打不开，然后就想写个分割器。code 贴到下面
code
import java.io.BufferedWriter;import java.io.File;import java.io.FileInputStream;import java.io.FileNotFoundException;import java.io.FileWriter;import java.io.IOException;import java.util.NoSuchElementException;import java.util.Scanner;public class FileSplit { public static String PATH = "D://FileSplit"; public static String FILE_NAME = "E://xxx//data//logs//LogWriterLog.txt"; public static int MAX_LINE_NUM = 100000; public static int FILE_INDEX = 1; public static void main(String[] args) { FileInputStream fis = null; FileWriter fw = null; BufferedWriter bw = null; try { File file = new File(FILE_NAME); fis = new FileInputStream(file); Scanner sc = new Scanner(fis); String nextLine = sc.nextLine(); String lineSeparator = System.getPRoperty("line.separator", "/r/n"); mkdirs(PATH); int i = 0; boolean needNewFile = true; while(nextLine != null){ if(i < MAX_LINE_NUM) { if(needNewFile) { File temp = new File(PATH + File.separator + FILE_INDEX + ".txt"); fw = new FileWriter(temp); bw = new BufferedWriter(fw); needNewFile = false; } bw.append(nextLine); bw.append(lineSeparator); i++; } else { bw.append(nextLine); bw.append(lineSeparator); bw.flush(); i = 0; needNewFile = true; FILE_INDEX ++; if(bw != null) { bw.close(); } if(fw != null) { fw.close(); } } try { nextLine = sc.nextLine(); } catch (NoSuchElementException e) { System.exit(0); } } } catch (FileNotFoundException e) { e.printStackTrace(); } catch (IOException e) { e.printStackTrace(); } finally { try { if(bw != null) { bw.close(); } if(fw != null) { fw.close(); } if(fis != null) { fis.close(); } } catch (IOException e) { e.printStackTrace(); } } } private static void mkdirs(String path) { File file = new File(path); if(!file.exists()){ file.mkdirs(); } }} Note代码很简单，但是要考虑内存问题，文件太大，如果都加载到内存很容易就OutOfMemory，所以我用了Scanner来扫描整个文件，这样只会扫描文件不会加载整个文件到内存，不用担心内存问题。
新闻热点
疑难解答
