我一直在试验各种Java代码,试图想出一些能够编码包含引号,空格和“异国情调”Unicode字符的字符串,并生成与JavaScript的encodeURIComponent函数相同的输出。 / p>
我的折磨测试字符串是:“A”B±“
如果我在Firebug中输入以下JavaScript语句:
encodeURIComponent('"A" B ± "');
- 然后我得到:
"%22A%22%20B%20%C2%B1%20%22"
这是我的小测试Java程序:
import java.io.UnsupportedEncodingException;
import java.net.URLEncoder;
public class EncodingTest
{
public static void main(String[] args) throws UnsupportedEncodingException
{
String s = "\"A\" B ± \"";
System.out.println("URLEncoder.encode returns "
+ URLEncoder.encode(s, "UTF-8"));
System.out.println("getBytes returns "
+ new String(s.getBytes("UTF-8"), "ISO-8859-1"));
}
}
- 该计划输出:
URLEncoder.encode returns %22A%22+B+%C2%B1+%22 getBytes returns "A" B ± "
关闭,但没有雪茄!使用Java对UTF-8字符串进行编码的最佳方法是什么,以便它生成与JavaScript encodeURIComponent
相同的输出?
编辑:我正在使用Java 1.4转移到Java 5。
答案 0 :(得分:108)
这是我最终提出的课程:
import java.io.UnsupportedEncodingException;
import java.net.URLDecoder;
import java.net.URLEncoder;
/**
* Utility class for JavaScript compatible UTF-8 encoding and decoding.
*
* @see http://stackoverflow.com/questions/607176/java-equivalent-to-javascripts-encodeuricomponent-that-produces-identical-output
* @author John Topley
*/
public class EncodingUtil
{
/**
* Decodes the passed UTF-8 String using an algorithm that's compatible with
* JavaScript's <code>decodeURIComponent</code> function. Returns
* <code>null</code> if the String is <code>null</code>.
*
* @param s The UTF-8 encoded String to be decoded
* @return the decoded String
*/
public static String decodeURIComponent(String s)
{
if (s == null)
{
return null;
}
String result = null;
try
{
result = URLDecoder.decode(s, "UTF-8");
}
// This exception should never occur.
catch (UnsupportedEncodingException e)
{
result = s;
}
return result;
}
/**
* Encodes the passed String as UTF-8 using an algorithm that's compatible
* with JavaScript's <code>encodeURIComponent</code> function. Returns
* <code>null</code> if the String is <code>null</code>.
*
* @param s The String to be encoded
* @return the encoded String
*/
public static String encodeURIComponent(String s)
{
String result = null;
try
{
result = URLEncoder.encode(s, "UTF-8")
.replaceAll("\\+", "%20")
.replaceAll("\\%21", "!")
.replaceAll("\\%27", "'")
.replaceAll("\\%28", "(")
.replaceAll("\\%29", ")")
.replaceAll("\\%7E", "~");
}
// This exception should never occur.
catch (UnsupportedEncodingException e)
{
result = s;
}
return result;
}
/**
* Private constructor to prevent this class from being instantiated.
*/
private EncodingUtil()
{
super();
}
}
答案 1 :(得分:54)
看看实施差异,我看到了:
[-a-zA-Z0-9._*~'()!]
Java 1.5.0 documentation on URLEncoder
:
[-a-zA-Z0-9._*]
" "
将转换为加号"+"
。 基本上,要获得所需的结果,请使用URLEncoder.encode(s, "UTF-8")
,然后进行一些后期处理:
"+"
替换为"%20"
"%xx"
的所有[~'()!]
替换回其文字对位答案 2 :(得分:12)
使用Java 6附带的javascript引擎:
import javax.script.ScriptEngine;
import javax.script.ScriptEngineManager;
public class Wow
{
public static void main(String[] args) throws Exception
{
ScriptEngineManager factory = new ScriptEngineManager();
ScriptEngine engine = factory.getEngineByName("JavaScript");
engine.eval("print(encodeURIComponent('\"A\" B ± \"'))");
}
}
产出:%22A%22%20B%20%c2%b1%20%22
情况有所不同,但它更接近你想要的。
答案 3 :(得分:5)
我使用java.net.URI#getRawPath()
,例如
String s = "a+b c.html";
String fixed = new URI(null, null, s, null).getRawPath();
fixed
的值为a+b%20c.html
,这就是您想要的。
对URLEncoder.encode()
的输出进行后处理将消除假设在URI中的任何优缺点。例如
URLEncoder.encode("a+b c.html").replaceAll("\\+", "%20");
将为您a%20b%20c.html
,其解释为a b c.html
。
答案 4 :(得分:4)
我提出了我自己的encodeURIComponent版本,因为发布的解决方案有一个问题,如果String中存在+,应编码,它将转换为空格。
所以这是我的班级:
import java.io.UnsupportedEncodingException;
import java.util.BitSet;
public final class EscapeUtils
{
/** used for the encodeURIComponent function */
private static final BitSet dontNeedEncoding;
static
{
dontNeedEncoding = new BitSet(256);
// a-z
for (int i = 97; i <= 122; ++i)
{
dontNeedEncoding.set(i);
}
// A-Z
for (int i = 65; i <= 90; ++i)
{
dontNeedEncoding.set(i);
}
// 0-9
for (int i = 48; i <= 57; ++i)
{
dontNeedEncoding.set(i);
}
// '()*
for (int i = 39; i <= 42; ++i)
{
dontNeedEncoding.set(i);
}
dontNeedEncoding.set(33); // !
dontNeedEncoding.set(45); // -
dontNeedEncoding.set(46); // .
dontNeedEncoding.set(95); // _
dontNeedEncoding.set(126); // ~
}
/**
* A Utility class should not be instantiated.
*/
private EscapeUtils()
{
}
/**
* Escapes all characters except the following: alphabetic, decimal digits, - _ . ! ~ * ' ( )
*
* @param input
* A component of a URI
* @return the escaped URI component
*/
public static String encodeURIComponent(String input)
{
if (input == null)
{
return input;
}
StringBuilder filtered = new StringBuilder(input.length());
char c;
for (int i = 0; i < input.length(); ++i)
{
c = input.charAt(i);
if (dontNeedEncoding.get(c))
{
filtered.append(c);
}
else
{
final byte[] b = charToBytesUTF(c);
for (int j = 0; j < b.length; ++j)
{
filtered.append('%');
filtered.append("0123456789ABCDEF".charAt(b[j] >> 4 & 0xF));
filtered.append("0123456789ABCDEF".charAt(b[j] & 0xF));
}
}
}
return filtered.toString();
}
private static byte[] charToBytesUTF(char c)
{
try
{
return new String(new char[] { c }).getBytes("UTF-8");
}
catch (UnsupportedEncodingException e)
{
return new byte[] { (byte) c };
}
}
}
答案 5 :(得分:3)
我想出了http://blog.sangupta.com/2010/05/encodeuricomponent-and.html记录的另一个实现。该实现还可以处理Unicode字节。
答案 6 :(得分:1)
这是一个简单的例子Ravi Wallau的解决方案:
public String buildSafeURL(String partialURL, String documentName)
throws ScriptException {
ScriptEngineManager scriptEngineManager = new ScriptEngineManager();
ScriptEngine scriptEngine = scriptEngineManager
.getEngineByName("JavaScript");
String urlSafeDocumentName = String.valueOf(scriptEngine
.eval("encodeURIComponent('" + documentName + "')"));
String safeURL = partialURL + urlSafeDocumentName;
return safeURL;
}
public static void main(String[] args) {
EncodeURIComponentDemo demo = new EncodeURIComponentDemo();
String partialURL = "https://www.website.com/document/";
String documentName = "Tom & Jerry Manuscript.pdf";
try {
System.out.println(demo.buildSafeURL(partialURL, documentName));
} catch (ScriptException se) {
se.printStackTrace();
}
}
<强>输出:强>
https://www.website.com/document/Tom%20%26%20Jerry%20Manuscript.pdf
它还回答了Loren Shqipognja关于如何将String变量传递给encodeURIComponent()
的评论中的悬而未决的问题。方法scriptEngine.eval()
返回Object
,因此可以通过String.valueOf()
等方法将其转换为String。
答案 7 :(得分:1)
这就是我正在使用的:
private static final String HEX = "0123456789ABCDEF";
public static String encodeURIComponent(String str) {
if (str == null) return null;
byte[] bytes = str.getBytes(StandardCharsets.UTF_8);
StringBuilder builder = new StringBuilder(bytes.length);
for (byte c : bytes) {
if (c >= 'a' ? c <= 'z' || c == '~' :
c >= 'A' ? c <= 'Z' || c == '_' :
c >= '0' ? c <= '9' : c == '-' || c == '.')
builder.append((char)c);
else
builder.append('%')
.append(HEX.charAt(c >> 4 & 0xf))
.append(HEX.charAt(c & 0xf));
}
return builder.toString();
}
根据RFC 3986,对每个不是非保留字符的字符进行百分比编码,从而超越了Javascript。
这是相反的转换:
public static String decodeURIComponent(String str) {
if (str == null) return null;
int length = str.length();
byte[] bytes = new byte[length / 3];
StringBuilder builder = new StringBuilder(length);
for (int i = 0; i < length; ) {
char c = str.charAt(i);
if (c != '%') {
builder.append(c);
i += 1;
} else {
int j = 0;
do {
char h = str.charAt(i + 1);
char l = str.charAt(i + 2);
i += 3;
h -= '0';
if (h >= 10) {
h |= ' ';
h -= 'a' - '0';
if (h >= 6) throw new IllegalArgumentException();
h += 10;
}
l -= '0';
if (l >= 10) {
l |= ' ';
l -= 'a' - '0';
if (l >= 6) throw new IllegalArgumentException();
l += 10;
}
bytes[j++] = (byte)(h << 4 | l);
if (i >= length) break;
c = str.charAt(i);
} while (c == '%');
builder.append(new String(bytes, 0, j, UTF_8));
}
}
return builder.toString();
}
答案 8 :(得分:0)
我从google-http-java-client库中找到了PercentEscaper类,可以很容易地用来实现encodeURIComponent。
PercentEscaper from google-http-java-client javadoc google-http-java-client home
答案 9 :(得分:0)
我已经成功使用了java.net.URI类:
public static String uriEncode(String string) {
String result = string;
if (null != string) {
try {
String scheme = null;
String ssp = string;
int es = string.indexOf(':');
if (es > 0) {
scheme = string.substring(0, es);
ssp = string.substring(es + 1);
}
result = (new URI(scheme, ssp, null)).toString();
} catch (URISyntaxException usex) {
// ignore and use string that has syntax error
}
}
return result;
}
答案 10 :(得分:0)
Guava图书馆有PercentEscaper:
Escaper percentEscaper = new PercentEscaper("-_.*", false);
&#34; -_ *&#34;是安全的角色
false说PercentEscaper用&#39;%20&#39;来逃避空间,而不是&#39; +&#39;
答案 11 :(得分:0)
对我来说这很有效:
import org.apache.http.client.utils.URIBuilder;
String encodedString = new URIBuilder()
.setParameter("i", stringToEncode)
.build()
.getRawQuery() // output: i=encodedString
.substring(2);
或使用其他UriBuilder
import javax.ws.rs.core.UriBuilder;
String encodedString = UriBuilder.fromPath("")
.queryParam("i", stringToEncode)
.toString() // output: ?i=encodedString
.substring(3);
在我看来,使用标准库是一个更好的想法,而不是手动后处理。同样@Chris的回答看起来不错,但它不适用于网址,例如“http://a+b c.html”
答案 12 :(得分:0)
我用过
String encodedUrl = new URI(null, url, null).toASCIIString();
编码网址。
要在url
中的现有参数之后添加参数,我使用UriComponentsBuilder