java字符串压缩_java字符串压缩 - jeff1989的个人页面 - OSCHINA - 中文开源技术交流社区...
最近在做电信的一个用户套餐使用积量查询的接口，查询出的结构是一大段字符串。为了减小网络传输，故将字符串采用jdk自带的gzip和zip方法进行压缩。并用apache common 的base64进行压缩字符串的转码。base64的转码需要导入apache的codec包，不要使用sun的base64转码包。
代码如下：
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;
import org.apache.commons.codec.binary.Base64;
/**
* author:jfhan
* desc:字符串压缩/解压工具，提供gzip和zip两种方式，压缩后的字符串使用base64转码
* */
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 String(new Base64().encode(out.toByteArray()));
}
/**
* 使用gzip进行解压缩
* @param compressedStr
* @return 解压后的字符串
*/
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 Base64().decode(compressedStr.getBytes());
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 String(new Base64().encode(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 Base64().decode(compressedStr.getBytes());
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;
}
}