字符串gzip压缩、解压

女爷i 2022-05-23 01:00 285阅读 0赞

package org.jc.plugins.gzip;
    
    
    import java.io.ByteArrayInputStream;
    import java.io.ByteArrayOutputStream;
    import java.io.IOException;
    import java.util.zip.GZIPInputStream;
    import java.util.zip.GZIPOutputStream;
    import java.util.zip.ZipEntry;
    import java.util.zip.ZipInputStream;
    import java.util.zip.ZipOutputStream;
    
    
    public class ZipUtils {
    
    
        /**
         * 
         * 使用gzip进行压缩
         */
        public static String gzip(String primStr) {
            if (primStr == null || primStr.length() == 0) {
                return primStr;
            }
    
    
            ByteArrayOutputStream out = new ByteArrayOutputStream();
    
    
            GZIPOutputStream gzip = null;
            try {
                gzip = new GZIPOutputStream(out);
                gzip.write(primStr.getBytes());
            } catch (IOException e) {
                e.printStackTrace();
            } finally {
                if (gzip != null) {
                    try {
                        gzip.close();
                    } catch (IOException e) {
                        e.printStackTrace();
                    }
                }
            }
    
    
            return new sun.misc.BASE64Encoder().encode(out.toByteArray());
        }
    
    
        /**
         *
         * <p>
         * Description:使用gzip进行解压缩
         * </p>
         * 
         * @param compressedStr
         * @return
         */
        public static String gunzip(String compressedStr) {
            if (compressedStr == null) {
                return null;
            }
    
    
            ByteArrayOutputStream out = new ByteArrayOutputStream();
            ByteArrayInputStream in = null;
            GZIPInputStream ginzip = null;
            byte[] compressed = null;
            String decompressed = null;
            try {
                compressed = new sun.misc.BASE64Decoder().decodeBuffer(compressedStr);
                in = new ByteArrayInputStream(compressed);
                ginzip = new GZIPInputStream(in);
    
    
                byte[] buffer = new byte[1024];
                int offset = -1;
                while ((offset = ginzip.read(buffer)) != -1) {
                    out.write(buffer, 0, offset);
                }
                decompressed = out.toString();
            } catch (IOException e) {
                e.printStackTrace();
            } finally {
                if (ginzip != null) {
                    try {
                        ginzip.close();
                    } catch (IOException e) {
                    }
                }
                if (in != null) {
                    try {
                        in.close();
                    } catch (IOException e) {
                    }
                }
                if (out != null) {
                    try {
                        out.close();
                    } catch (IOException e) {
                    }
                }
            }
    
    
            return decompressed;
        }
    
    
        /**
         * 使用zip进行压缩
         * 
         * @param str
         *            压缩前的文本
         * @return 返回压缩后的文本
         */
        public static final String zip(String str) {
            if (str == null)
                return null;
            byte[] compressed;
            ByteArrayOutputStream out = null;
            ZipOutputStream zout = null;
            String compressedStr = null;
            try {
                out = new ByteArrayOutputStream();
                zout = new ZipOutputStream(out);
                zout.putNextEntry(new ZipEntry("0"));
                zout.write(str.getBytes());
                zout.closeEntry();
                compressed = out.toByteArray();
                compressedStr = new sun.misc.BASE64Encoder().encodeBuffer(compressed);
            } catch (IOException e) {
                compressed = null;
            } finally {
                if (zout != null) {
                    try {
                        zout.close();
                    } catch (IOException e) {
                    }
                }
                if (out != null) {
                    try {
                        out.close();
                    } catch (IOException e) {
                    }
                }
            }
            return compressedStr;
        }
    
    
        /**
         * 使用zip进行解压缩
         * 
         * @param compressed
         *            压缩后的文本
         * @return 解压后的字符串
         */
        public static final String unzip(String compressedStr) {
            if (compressedStr == null) {
                return null;
            }
    
    
            ByteArrayOutputStream out = null;
            ByteArrayInputStream in = null;
            ZipInputStream zin = null;
            String decompressed = null;
            try {
                byte[] compressed = new sun.misc.BASE64Decoder().decodeBuffer(compressedStr);
                out = new ByteArrayOutputStream();
                in = new ByteArrayInputStream(compressed);
                zin = new ZipInputStream(in);
                zin.getNextEntry();
                byte[] buffer = new byte[1024];
                int offset = -1;
                while ((offset = zin.read(buffer)) != -1) {
                    out.write(buffer, 0, offset);
                }
                decompressed = out.toString();
            } catch (IOException e) {
                decompressed = null;
            } finally {
                if (zin != null) {
                    try {
                        zin.close();
                    } catch (IOException e) {
                    }
                }
                if (in != null) {
                    try {
                        in.close();
                    } catch (IOException e) {
                    }
                }
                if (out != null) {
                    try {
                        out.close();
                    } catch (IOException e) {
                    }
                }
            }
            return decompressed;
        }
    }