Java ??? ?? ?? ?? ??? ???? ?? ?? ?? ? ??, ???? ?? ??? ?????

Java ?? ???? ??? ??? ??? ?? ??? ?? ???? ???. ??? ??? ?? ? ?? ??? ?? ?? ???? ?? ??? ???? ?? ?? ??? ?? ??? ??? ? ????. ?? ??? ??? ????? ? ?? ??? ??? ??? ???? ???. ? ????? ?? ?? ??? ?? ????? ???? ? ?? ???? ?????.

1. BufferedReader ? FileReader ??
   BufferedReader ? FileReader? Java IO ??????? ?? ???? ?? ???? ???? ?? ?? ??? ?????. ?? ???? ??? ????? ???? ?? ??? ??? ? ?? ?? ? ????.

import java.io.BufferedReader;
import java.io.FileReader;
import java.io.IOException;

public class ReadLargeFile {
    public static void main(String[] args) {
        BufferedReader reader = null;
        try {
            reader = new BufferedReader(new FileReader("path/to/large/file.txt"));
            String line;
            while ((line = reader.readLine()) != null) {
                // 處理每一行的邏輯
            }
        } catch (IOException e) {
            e.printStackTrace();
        } finally {
            try {
                if (reader != null) {
                    reader.close();
                }
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
    }
}

2. RandomAccessFile ??
   RandomAccessFile? ??? ?? ??? ???? ???? ? ?? ????? ???? ? ?? ?? ?? ?????. ???? ??? ?????? ?? ??? ?? ???? ??? ??? ????? ?? ??? ??? ? ????.

import java.io.IOException;
import java.io.RandomAccessFile;

public class ReadLargeFile {
    public static void main(String[] args) {
        RandomAccessFile file = null;
        try {
            file = new RandomAccessFile("path/to/large/file.txt", "r");
            long fileLength = file.length();
            int bufferSize = 1024; // 緩沖區(qū)大小
            byte[] buffer = new byte[bufferSize];
            long startPosition = 0; // 起始位置
            long endPosition; // 結(jié)束位置

            // 分段讀取文件內(nèi)容
            while (startPosition < fileLength) {
                file.seek(startPosition); // 設(shè)置文件指針的位置
                int readSize = file.read(buffer); // 讀取字節(jié)到緩沖區(qū)
                endPosition = startPosition + readSize; // 計(jì)算結(jié)束位置

                // 處理讀取的字節(jié)流
                for (int i = 0; i < readSize; i++) {
                    // 處理每個(gè)字節(jié)的邏輯
                }

                startPosition = endPosition; // 更新起始位置
            }
        } catch (IOException e) {
            e.printStackTrace();
        } finally {
            try {
                if (file != null) {
                    file.close();
                }
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
    }
}

3. NIO(??? IO) ??
   ?? IO ??? ???? NIO? ??? ?? ? ???? ??? ?????. NIO? ??? ??? ???? ??? ?? ?? ??? ??? ? ????.

import java.io.FileInputStream;
import java.io.IOException;
import java.nio.ByteBuffer;
import java.nio.channels.FileChannel;

public class ReadLargeFile {
    public static void main(String[] args) {
        FileInputStream fileInputStream = null;
        FileChannel fileChannel = null;
        try {
            fileInputStream = new FileInputStream("path/to/large/file.txt");
            fileChannel = fileInputStream.getChannel();
            ByteBuffer buffer = ByteBuffer.allocate(1024); // 緩沖區(qū)大小

            while (fileChannel.read(buffer) != -1) {
                buffer.flip(); // 準(zhǔn)備讀模式
                while (buffer.hasRemaining()) {
                    // 處理每個(gè)字節(jié)的邏輯
                }
                buffer.clear(); // 清除緩沖區(qū)
            }
        } catch (IOException e) {
            e.printStackTrace();
        } finally {
            try {
                if (fileChannel != null) {
                    fileChannel.close();
                }
                if (fileInputStream != null) {
                    fileInputStream.close();
                }
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
    }
}

?? Java ??? ?? ?? ??? ???? ?? ????? ???? ? ?? ?? ? ?????. ? ???? ?? ??? ????? ????. ??? ??? ??? ???? ???? ???? ??? ?? ?? ??? ?? ????? ???? ??? ????? ?? ??? ??? ? ????. ? ??? ??? ?? ??? ??? ??? ? ? ???? ???? ? ??? ??? ????.

? ??? ?? ?? ? ??: Java ?? ??? ?? ?? ?? ??? ?? ?????. ??? ??? PHP ??? ????? ?? ?? ??? ?????!