解析SpringBoot项目开发之Gzip压缩过程

gzip on;
gzip_min_length 1k;
gzip_buffers 4 16k;
#gzip_http_version 1.0;
gzip_comp_level 2;
gzip_types text/plain application/x-javascript text/css application/xml text/javascript application/x-httpd-php image/jpeg image/gif image/png;
gzip_vary off;

import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.util.zip.GZIPInputStream;
import java.util.zip.GZIPOutputStream;
import org.apache.commons.codec.binary.StringUtils;
 
public class GZIPUtils {
 
  public static final String GZIP_ENCODE_UTF_8 = "UTF-8";
  public static final String GZIP_ENCODE_ISO_8859_1 = "ISO-8859-1";
 
  /**
   * 字符串压缩为GZIP字节数组
   * @param str
   * @return
   */
  public static byte[] compress(String str) {
    return compress(str, GZIP_ENCODE_UTF_8);
  }
 
  /**
   * 字符串压缩为GZIP字节数组
   * @param str
   * @param encoding
   * @return
   */
  public static byte[] compress(String str, String encoding) {
    if (str == null || str.length() == 0) {
      return null;
    }
    ByteArrayOutputStream out = new ByteArrayOutputStream();
    GZIPOutputStream gzip;
    try {
      gzip = new GZIPOutputStream(out);
      gzip.write(str.getBytes(encoding));
      gzip.close();
    } catch (IOException e) {
      e.printStackTrace();
    }
    return out.toByteArray();
  }
 
  /**
   * GZIP解压缩
   * @param bytes
   * @return
   */
  public static byte[] uncompress(byte[] bytes) {
    if (bytes == null || bytes.length == 0) {
      return null;
    }
    ByteArrayOutputStream out = new ByteArrayOutputStream();
    ByteArrayInputStream in = new ByteArrayInputStream(bytes);
    try {
      GZIPInputStream ungzip = new GZIPInputStream(in);
      byte[] buffer = new byte[256];
      int n;
      while ((n = ungzip.read(buffer)) >= 0) {
        out.write(buffer, 0, n);
      }
    } catch (IOException e) {
      e.printStackTrace();
    }
    return out.toByteArray();
  }
 
  /**
   * 解压并返回String
   * @param bytes
   * @return
   */
  public static String uncompressToString(byte[] bytes) {
    return uncompressToString(bytes, GZIP_ENCODE_UTF_8);
  }
 
  /**
   * 解压
   * @param bytes
   * @param encoding
   * @return
   */
  public static String uncompressToString(byte[] bytes, String encoding) {
    if (bytes == null || bytes.length == 0) {
      return null;
    }
    ByteArrayOutputStream out = new ByteArrayOutputStream();
    ByteArrayInputStream in = new ByteArrayInputStream(bytes);
    try {
      GZIPInputStream ungzip = new GZIPInputStream(in);
      byte[] buffer = new byte[256];
      int n;
      while ((n = ungzip.read(buffer)) >= 0) {
        out.write(buffer, 0, n);
      }
      return out.toString(encoding);
    } catch (IOException e) {
      e.printStackTrace();
    }
    return null;
  }
 
  public static void main(String[] args) {
    String str = "%5B%7B%22lastUpdateTime%22%3A%222011-10-28+9%3A39%3A41%22%2C%22smsList%22%3A%5B%7B%22liveState%22%3A%221";
    System.out.println("原长度：" + str.length());
    System.out.println("压缩后字符串：" + GZIPUtils.compress(str).toString().length());
    System.out.println("解压缩后字符串：" + StringUtils.newStringUtf8(GZIPUtils.uncompress(GZIPUtils.compress(str))));
    System.out.println("解压缩后字符串：" + GZIPUtils.uncompressToString(GZIPUtils.compress(str)));
  }
}