zlib 介绍

有关ZLib可参见官方主页 http://www.zlib.net/
ZLib可以简单的理解为 数据 压缩、解压缩算法，如：对字节数组进行压缩

与 zip 不同，zip可以对文件、目录进行压缩

代码

package top.malaoshi.util;

import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.util.zip.*;

public class ZLibUtils {
    static final int MAX_LEN = 1024 * 8;
    /**
     * 压缩
     *
     * @param data
     *            待压缩数据
     * @return byte[] 压缩后的数据
     */
    public static byte[] compress(byte[] data) throws IOException {
        byte[] output = null;

        Deflater compresser = new Deflater();

        compresser.reset();
        compresser.setInput(data);
        compresser.finish();
        ByteArrayOutputStream bos = new ByteArrayOutputStream(data.length);
        try {
            byte[] buf = new byte[MAX_LEN];
            while (!compresser.finished()) {
                int i = compresser.deflate(buf);
                bos.write(buf, 0, i);
            }
            output = bos.toByteArray();
        }  finally {

            bos.close();

        }
        compresser.end();
        return output;
    }

    /**
     * 压缩
     *
     * @param data 待压缩数据
     *
     * @param os 输出流
     */
    public static void compress(byte[] data, OutputStream os) throws IOException {
        DeflaterOutputStream dos = new DeflaterOutputStream(os);
        dos.write(data, 0, data.length);
        dos.finish();
        dos.flush();
        dos.close();

    }

    /**
     * 解压缩
     *
     * @param data
     *            待压缩的数据
     * @return byte[] 解压缩后的数据
     */
    public static byte[] decompress(byte[] data) throws IOException, DataFormatException {
        byte[] output = null;

        Inflater decompresser = new Inflater();
        decompresser.reset();
        decompresser.setInput(data);

        ByteArrayOutputStream o = new ByteArrayOutputStream(data.length);
        try {
            byte[] buf = new byte[MAX_LEN];
            while (!decompresser.finished()) {
                int i = decompresser.inflate(buf);
                o.write(buf, 0, i);
            }
            output = o.toByteArray();
        }  finally {

            o.close();
        }

        decompresser.end();
        return output;
    }

    /**
     * 解压缩
     *
     * @param is
     *            输入流
     * @return byte[] 解压缩后的数据
     */
    public static byte[] decompress(InputStream is) throws IOException {
        InflaterInputStream iis = new InflaterInputStream(is);
        ByteArrayOutputStream o = new ByteArrayOutputStream(MAX_LEN);
        try {
            int i = MAX_LEN;
            byte[] buf = new byte[i];

            while ((i = iis.read(buf, 0, i)) > 0) {
                o.write(buf, 0, i);
            }

        } catch (IOException e) {
            throw e;
        } finally {
            iis.close();
            o.close();
        }
        return o.toByteArray();
    }
}

参考：

https://blog.csdn.net/wxyFighting/article/details/9075505

原文出处：/show_1IX5yDnsOTD5.html