Java:大文件拆分工具

时间:2023-03-09 05:16:09
Java:大文件拆分工具

java大文件拆分工具(过滤掉表头)

import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.FileReader;
import java.io.FileWriter;
import java.io.IOException; public class SplitTools {
public static void main(String[] args) throws IOException {
// "E:\\eutranrelation.csv";
String bigFilePath = args[0];
// "E:\\eutranrelation-%s.csv";
String splitFileParttern = args[1];
//
int splitFileCount = Integer.valueOf(args[2]); BufferedReader reader = new BufferedReader(new FileReader(bigFilePath));
String header = reader.readLine();
int totalLine = 0;
if (header != null) {
String line = null;
while ((line = reader.readLine()) != null) {
totalLine++;
}
} reader.close(); int splitFileTotalLines = totalLine / splitFileCount;
int generateFileIdx = 0; BufferedWriter bufferedWriter = null;
reader = new BufferedReader(new FileReader(bigFilePath));
header = reader.readLine();
int currentIdx = 0;
if (header != null) {
String line = null;
while ((line = reader.readLine()) != null) {
if (currentIdx == 0) {
String filePath = String.format(splitFileParttern,
String.valueOf(generateFileIdx));
bufferedWriter = new BufferedWriter(
new FileWriter(filePath));
} bufferedWriter.write(line + "\r\n"); currentIdx++; if (currentIdx == splitFileTotalLines) {
generateFileIdx++;
if (generateFileIdx != splitFileCount) {
currentIdx = 0;
bufferedWriter.flush();
bufferedWriter.close();
}
}
} if (bufferedWriter != null) {
bufferedWriter.flush();
bufferedWriter.close();
}
} reader.close(); System.out.println("The total number of documents is:" + totalLine);
}
}