在Java中将数组字符串转换为字符串并返回
我在Java中有一个数组字符串[],必须首先将其编码/转换为字符串,然后在代码中进一步将其转换回字符串[]数组。问题是,我可以在string[]数组中的字符串中包含任何字符,因此在编码时必须非常小心。解码所需的所有信息都必须在最后一个字符串中。我不能在额外变量中返回字符串和其他信息 到目前为止,我设计的算法是:在Java中将数组字符串转换为字符串并返回,java,string,encoding,Java,String,Encoding,我在Java中有一个数组字符串[],必须首先将其编码/转换为字符串,然后在代码中进一步将其转换回字符串[]数组。问题是,我可以在string[]数组中的字符串中包含任何字符,因此在编码时必须非常小心。解码所需的所有信息都必须在最后一个字符串中。我不能在额外变量中返回字符串和其他信息 到目前为止,我设计的算法是: 将所有字符串相邻附加,例如: 字符串[]a={“lala”,“exe”,“a”} 进入 字符串b=“laexea” 在字符串末尾追加字符串[]中所有字符串的长度,以$符号与正文分隔,然后
干杯 只需使用一个已知的分隔符(如
@
或#
来附加字符串),然后使用yourString.split(yourselder)从中获取一个数组。我将使用单词之间的符号,稍后使用String#split
方法来获取字符串。根据您的$
符号示例,它是
public String mergeStrings(String[] ss) {
StringBuilder sb = new StringBuilder();
for(String s : ss) {
sb.append(s);
sb.append('$');
}
return sb.toString();
}
public String[] unmergeStrings(String s) {
return s.split("\\$");
}
注意,在本例中,我在$
符号之前添加了一个双精度\
,因为String#split
方法接收一个正则表达式作为参数,$
符号是regex中的一个特殊字符
public String processData(String[] ss) {
String mergedString = mergeStrings(ss);
//process data...
//a little example...
for(int i = 0; i < mergedString.length(); i++) {
if (mergedString.charAt(i) == '$') {
System.out.println();
} else {
System.out.print(mergedString.charAt(i));
}
}
System.out.println();
//unmerging the data again
String[] oldData = unmergeStrings(mergedString);
}
如果您不想在字符串操作上花费太多时间,可以使用java serialization+,如下所示:
public void stringArrayTest() throws IOException, ClassNotFoundException, DecoderException {
String[] strs = new String[] {"test 1", "test 2", "test 3"};
System.out.println(Arrays.toString(strs));
// serialize
ByteArrayOutputStream out = new ByteArrayOutputStream();
new ObjectOutputStream(out).writeObject(strs);
// your string
String yourString = new String(Hex.encodeHex(out.toByteArray()));
System.out.println(yourString);
// deserialize
ByteArrayInputStream in = new ByteArrayInputStream(Hex.decodeHex(yourString.toCharArray()));
System.out.println(Arrays.toString((String[]) new ObjectInputStream(in).readObject()));
}
这将返回以下输出:
[test 1, test 2, test 3]
aced0005757200135b4c6a6176612e6c616e672e537472696e673badd256e7e91d7b47020000787000000003740006746573742031740006746573742032740006746573742033
[test 1, test 2, test 3]
如果您使用的是maven,则可以对commons编解码器使用以下依赖项:
<dependency>
<groupId>commons-codec</groupId>
<artifactId>commons-codec</artifactId>
<version>1.2</version>
</dependency>
对于Base64,对于下面公开的代码,结果字符串更短:
[test 1, test 2, test 3]
rO0ABXVyABNbTGphdmEubGFuZy5TdHJpbmc7rdJW5+kde0cCAAB4cAAAAAN0AAZ0ZXN0IDF0AAZ0ZXN0IDJ0AAZ0ZXN0IDM=
[test 1, test 2, test 3]
关于每种方法的时间,我对每种方法执行10^5次,结果如下:
- 字符串操作:156毫秒
- 十六进制:376毫秒
- Base64:379毫秒
import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.io.ObjectOutputStream;
import java.util.StringTokenizer;
import org.apache.commons.codec.DecoderException;
import org.apache.commons.codec.binary.Base64;
import org.apache.commons.codec.binary.Hex;
public class StringArrayRepresentationTest {
public static void main(String[] args) throws IOException, ClassNotFoundException, DecoderException {
String[] strs = new String[] {"test 1", "test 2", "test 3"};
long t = System.currentTimeMillis();
for (int i =0; i < 100000;i++) {
stringManipulation(strs);
}
System.out.println("String manipulation: " + (System.currentTimeMillis() - t));
t = System.currentTimeMillis();
for (int i =0; i < 100000;i++) {
testHex(strs);
}
System.out.println("Hex: " + (System.currentTimeMillis() - t));
t = System.currentTimeMillis();
for (int i =0; i < 100000;i++) {
testBase64(strs);
}
System.out.println("Base64: " + (System.currentTimeMillis() - t));
}
public static void stringManipulation(String[] strs) {
String result = serialize(strs);
unserialize(result);
}
private static String[] unserialize(String result) {
int sizesSplitPoint = result.toString().lastIndexOf('$');
String sizes = result.substring(sizesSplitPoint+1);
StringTokenizer st = new StringTokenizer(sizes, ";");
String[] resultArray = new String[st.countTokens()];
int i = 0;
int lastPosition = 0;
while (st.hasMoreTokens()) {
String stringLengthStr = st.nextToken();
int stringLength = Integer.parseInt(stringLengthStr);
resultArray[i++] = result.substring(lastPosition, lastPosition + stringLength);
lastPosition += stringLength;
}
return resultArray;
}
private static String serialize(String[] strs) {
StringBuilder sizes = new StringBuilder("$");
StringBuilder result = new StringBuilder();
for (String str : strs) {
if (sizes.length() != 1) {
sizes.append(';');
}
sizes.append(str.length());
result.append(str);
}
result.append(sizes.toString());
return result.toString();
}
public static void testBase64(String[] strs) throws IOException, ClassNotFoundException, DecoderException {
// serialize
ByteArrayOutputStream out = new ByteArrayOutputStream();
new ObjectOutputStream(out).writeObject(strs);
// your string
String yourString = new String(Base64.encodeBase64(out.toByteArray()));
// deserialize
ByteArrayInputStream in = new ByteArrayInputStream(Base64.decodeBase64(yourString.getBytes()));
}
public static void testHex(String[] strs) throws IOException, ClassNotFoundException, DecoderException {
// serialize
ByteArrayOutputStream out = new ByteArrayOutputStream();
new ObjectOutputStream(out).writeObject(strs);
// your string
String yourString = new String(Hex.encodeHex(out.toByteArray()));
// deserialize
ByteArrayInputStream in = new ByteArrayInputStream(Hex.decodeHex(yourString.toCharArray()));
}
}
import java.io.ByteArrayInputStream;
导入java.io.ByteArrayOutputStream;
导入java.io.IOException;
导入java.io.ObjectOutputStream;
导入java.util.StringTokenizer;
导入org.apache.commons.codec.DecoderException;
导入org.apache.commons.codec.binary.Base64;
导入org.apache.commons.codec.binary.Hex;
公共类StringArrayRepresentationTest{
publicstaticvoidmain(字符串[]args)抛出IOException、ClassNotFoundException、DecoderException{
字符串[]strs=新字符串[]{“测试1”、“测试2”、“测试3”};
long t=System.currentTimeMillis();
对于(int i=0;i<100000;i++){
字符串操纵(strs);
}
System.out.println(“字符串操作:”+(System.currentTimeMillis()-t));
t=System.currentTimeMillis();
对于(int i=0;i<100000;i++){
testHex(strs);
}
System.out.println(“十六进制:”+(System.currentTimeMillis()-t));
t=System.currentTimeMillis();
对于(int i=0;i<100000;i++){
testBase64(strs);
}
System.out.println(“Base64:”+(System.currentTimeMillis()-t));
}
公共静态void stringManipulation(String[]strs){
字符串结果=序列化(strs);
未序列化(结果);
}
私有静态字符串[]未序列化(字符串结果){
int-sizesSplitPoint=result.toString().lastIndexOf(“$”);
字符串大小=结果.子字符串(sizesSplitPoint+1);
StringTokenizer st=新的StringTokenizer(大小,“;”);
String[]resultArray=新字符串[st.countTokens()];
int i=0;
int lastPosition=0;
而(st.hasMoreTokens()){
字符串stringLengthStr=st.nextToken();
int stringLength=Integer.parseInt(stringLengthStr);
resultArray[i++]=结果.子字符串(lastPosition,lastPosition+stringLength);
lastPosition+=字符串长度;
}
返回结果数组;
}
私有静态字符串序列化(字符串[]strs){
StringBuilder尺寸=新StringBuilder($);
StringBuilder结果=新建StringBuilder();
用于(字符串str:strs){
如果(size.length()!=1){
大小。追加(“;”);
}
大小。追加(str.length());
结果:追加(str);
}
result.append(size.toString());
返回result.toString();
}
公共静态void testBase64(字符串[]strs)引发IOException、ClassNotFoundException、DecodeException{
//连载
ByteArrayOutputStream out=新建ByteArrayOutputStream();
新的ObjectOutputStream(out).writeObject(strs);
//你的绳子
String yourString=新字符串(Base64.encodeBase64(out.toByteArray());
//反序列化
ByteArrayInputStream in=newbytearrayinputstream(Base64.decodeBase64(yourString.getBytes());
}
公共静态void testHex(字符串[]strs)抛出IOException、ClassNotFoundException、DecoderException{
//连载
ByteArrayOutputStream out=新建ByteArrayOutputStream();
新的ObjectOutputStream(out).writeObject(strs);
//你的绳子
String yourString=新字符串(Hex.encodeHex(out.toByteArray());
//反序列化
ByteArrayInputStream in=新的ByteArrayInputStream(Hex.decodeHex(yourString.toCharArray());
}
}
使用类似Jackson的Json解析器来序列化/反序列化其他类型的对象,以及integer/Float ext到字符串和返回 OP解释说,在string[]数组中,他可以有字符串中的任何字符,因此在加入之前应该转义所选的分隔符,例如s.replaceAll(“\\$”,“\$”)
@sp00m我希望数据保持不变,而不是建议
[test 1, test 2, test 3]
rO0ABXVyABNbTGphdmEubGFuZy5TdHJpbmc7rdJW5+kde0cCAAB4cAAAAAN0AAZ0ZXN0IDF0AAZ0ZXN0IDJ0AAZ0ZXN0IDM=
[test 1, test 2, test 3]
import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.io.ObjectOutputStream;
import java.util.StringTokenizer;
import org.apache.commons.codec.DecoderException;
import org.apache.commons.codec.binary.Base64;
import org.apache.commons.codec.binary.Hex;
public class StringArrayRepresentationTest {
public static void main(String[] args) throws IOException, ClassNotFoundException, DecoderException {
String[] strs = new String[] {"test 1", "test 2", "test 3"};
long t = System.currentTimeMillis();
for (int i =0; i < 100000;i++) {
stringManipulation(strs);
}
System.out.println("String manipulation: " + (System.currentTimeMillis() - t));
t = System.currentTimeMillis();
for (int i =0; i < 100000;i++) {
testHex(strs);
}
System.out.println("Hex: " + (System.currentTimeMillis() - t));
t = System.currentTimeMillis();
for (int i =0; i < 100000;i++) {
testBase64(strs);
}
System.out.println("Base64: " + (System.currentTimeMillis() - t));
}
public static void stringManipulation(String[] strs) {
String result = serialize(strs);
unserialize(result);
}
private static String[] unserialize(String result) {
int sizesSplitPoint = result.toString().lastIndexOf('$');
String sizes = result.substring(sizesSplitPoint+1);
StringTokenizer st = new StringTokenizer(sizes, ";");
String[] resultArray = new String[st.countTokens()];
int i = 0;
int lastPosition = 0;
while (st.hasMoreTokens()) {
String stringLengthStr = st.nextToken();
int stringLength = Integer.parseInt(stringLengthStr);
resultArray[i++] = result.substring(lastPosition, lastPosition + stringLength);
lastPosition += stringLength;
}
return resultArray;
}
private static String serialize(String[] strs) {
StringBuilder sizes = new StringBuilder("$");
StringBuilder result = new StringBuilder();
for (String str : strs) {
if (sizes.length() != 1) {
sizes.append(';');
}
sizes.append(str.length());
result.append(str);
}
result.append(sizes.toString());
return result.toString();
}
public static void testBase64(String[] strs) throws IOException, ClassNotFoundException, DecoderException {
// serialize
ByteArrayOutputStream out = new ByteArrayOutputStream();
new ObjectOutputStream(out).writeObject(strs);
// your string
String yourString = new String(Base64.encodeBase64(out.toByteArray()));
// deserialize
ByteArrayInputStream in = new ByteArrayInputStream(Base64.decodeBase64(yourString.getBytes()));
}
public static void testHex(String[] strs) throws IOException, ClassNotFoundException, DecoderException {
// serialize
ByteArrayOutputStream out = new ByteArrayOutputStream();
new ObjectOutputStream(out).writeObject(strs);
// your string
String yourString = new String(Hex.encodeHex(out.toByteArray()));
// deserialize
ByteArrayInputStream in = new ByteArrayInputStream(Hex.decodeHex(yourString.toCharArray()));
}
}