是否有适用于 LZ4 和 ZStd 的最佳 Java 压缩库。我尝试过使用 apache commons(这是 zstd-jni 实现)
String fileURL = TestFileUtil.getFileURL(TestFileCategory.SMALL);
String outputFileName = TestFileUtil.BASE_DIR+"/zstd-"+(Math.random()*10)+".x";
System.out.println(Paths.get(fileURL));
printFileInfo(fileURL);
StopWatch watch = new StopWatch();
InputStream in = Files.newInputStream(Paths.get(fileURL));
OutputStream fout = Files.newOutputStream(Paths.get(outputFileName));
BufferedOutputStream out = new BufferedOutputStream(fout);
ZstdCompressorOutputStream zOut = new ZstdCompressorOutputStream(out);
int buffersize = 1024*4;
watch.mark();
final byte[] buffer = new byte[buffersize];
int n = 0;
while (-1 != (n = in.read(buffer))) {
zOut.write(buffer, 0, n);
}
zOut.close();
in.close();
但是这段代码不起作用它抛出
Exception in thread "main" java.lang.NoClassDefFoundError: com/github/luben/zstd/ZstdOutputStream
at org.apache.commons.compress.compressors.zstandard.ZstdCompressorOutputStream.<init>(ZstdCompressorOutputStream.java:83)
at com.zoho.test.testzstd.main(testzstd.java:28)
Caused by: java.lang.ClassNotFoundException: com.github.luben.zstd.ZstdOutputStream
at java.net.URLClassLoader.findClass(URLClassLoader.java:381)
at java.lang.ClassLoader.loadClass(ClassLoader.java:424)
at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:331)
at java.lang.ClassLoader.loadClass(ClassLoader.java:357)
... 2 more
对于 LZ4,我只是将 ZStdCompressorOutputStream 替换为
FramedLZ4CompressorOutputStream lzOut = new FramedLZ4CompressorOutputStream(out);
但压缩 2.4GB (csv) 文件花了将近 2 小时(尚未完成)。 代码有什么问题吗?或任何其他建议?
对于
zstd
,Java 有@luben 的 zstd-jni :
https://github.com/luben/zstd-jni
如果您更喜欢 Java 原生,@martint 在 Java 中有一个完整的端口(尽管功能较少): https://github.com/airlift/aircompressor/tree/master/src/main/java/io/airlift/compress/zstd
对于 LZ4,常见的绑定是:https://github.com/lz4/lz4-java, 不过,如果您更喜欢与
lz4
CLI 兼容的实现,则 Apache Commons 版本更可取。
这些库通常不能仅通过更改一个调用名称来交换。请参阅他们的文档或示例以了解它们的工作原理。
import com.github.luben.zstd.Zstd;
public class ZSTD {
public static void main(String[] args) {
// Zstd zstd = new Zstd();
System.out.println("Default compress level:" + Zstd.defaultCompressionLevel());
try {
//1.File operation
byte[] src = File2ByteArray.toByteArray("D:\\works\\ZSTD\\data\\data.bin1");
src = File2ByteArray.toByteArray("D:\\works\\ZSTD\\data\\aa.txt.zst");
byte[] des = new byte[src.length/4];
System.out.println("src length" + src.length);
Zstd.decompress(des, src);
System.out.println( "result:" +new String(des) );
//2
String data = "ABC";
byte[] strSrc = Zstd.compress(data.getBytes());
//byte[] strDest = new byte[ strSrc.length ];
byte[] strDest = new byte[strSrc.length/4];
Zstd.decompress( strDest, strSrc );
} catch (Exception ex) {
ex.printStackTrace();
}
}
}