在Java语言中使用LZ4添加到现有的压缩文件( .lz4

import net.jpountz.lz4.*;

import java.io.*;

public class LZ4AddToExistingFile {

    public static void main(String[] args) {
        String inputFilePath = "existing_compressed_file.lz4"; // 压缩文件的路径
        String dataToAdd = "New data to add"; // 要添加的数据

        // 读取现有压缩文件中的数据
        byte[] existingData = readExistingData(inputFilePath);

        // 创建LZ4压缩器和解压器
        LZ4Compressor compressor = LZ4Factory.fastestInstance().fastCompressor();
        LZ4FastDecompressor decompressor = LZ4Factory.fastestInstance().fastDecompressor();

        try {
            // 创建一个临时文件，用于存储解压缩后的数据
            File tempFile = File.createTempFile("temp", null);

            // 解压缩现有数据到临时文件
            decompressData(existingData, tempFile);

            // 打开临时文件和目标文件，用于写入新数据
            try (FileWriter fileWriter = new FileWriter(tempFile, true);
                 BufferedWriter bufferedWriter = new BufferedWriter(fileWriter)) {
                bufferedWriter.write(dataToAdd);
            }

            // 读取临时文件的数据
            byte[] newData = readTempFileData(tempFile);

            // 压缩新数据
            byte[] compressedData = compressData(newData, compressor);

            // 将压缩后的新数据和现有数据写入目标文件
            writeOutputFile(existingData, compressedData, inputFilePath);
        } catch (IOException e) {
            e.printStackTrace();
        }
    }

    // 读取现有文件的数据
    private static byte[] readExistingData(String filePath) {
        try (FileInputStream inputStream = new FileInputStream(filePath)) {
            return inputStream.readAllBytes();
        } catch (IOException e) {
            e.printStackTrace();
        }
        return new byte[0];
    }

    // 解压缩数据到指定文件
    private static void decompressData(byte[] compressedData, File outputFile) {
        try (LZ4FastDecompressor decompressor = LZ4Factory.fastestInstance().fastDecompressor();
             FileOutputStream outputStream = new FileOutputStream(outputFile)) {
            byte[] decompressedData = new byte[1024];
            int decompressedLength = decompressor.decompress(compressedData, decompressedData);
            outputStream.write(decompressedData, 0, decompressedLength);
        } catch (IOException e) {
            e.printStackTrace();
        }
    }

    // 读取临时文件的数据
    private static byte[] readTempFileData(File tempFile) {
        try (FileInputStream inputStream = new FileInputStream(tempFile)) {
            return inputStream.readAllBytes();
        } catch (IOException e) {
            e.printStackTrace();
        }
        return new byte[0];
    }

    // 压缩数据
    private static byte[] compressData(byte[] data, LZ4Compressor compressor) {
        int maxCompressedLength = compressor.maxCompressedLength(data.length);
        byte[] compressedData = new byte[maxCompressedLength];
        compressor.compress(data, 0, data.length, compressedData, 0, maxCompressedLength);
        return compressedData;
    }

    // 将现有数据和新数据写入目标文件
    private static void writeOutputFile(byte[] existingData, byte[] newData, String filePath) {
        try (FileOutputStream outputStream = new FileOutputStream(filePath)) {
            outputStream.write(existingData);
            outputStream.write(newData);
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
}

<dependency>
    <groupId>net.jpountz.lz4</groupId>
    <artifactId>lz4</artifactId>
    <version>1.4.0</version>
</dependency>