在 Java 中将字符串转换为 URL 标准字符串

Question

我有一个字符串，例如：

Cerepedia, una apliación web

我想将其转换为有效的 URL，例如：

Cerepedia,unaaplicacionweb

注意：特殊字符转换和空格去除。

顺便问一下，网址中可以使用逗号吗？

Answer 1

你看过URLEncoder吗？这似乎做了你需要它做的事情。虽然特殊字符将被转换为转义实体，而不是从它们的“特殊”属性中剥离。

Answer 2

在下面的类中尝试 convertNonAscii()

public class AsciiUtils {

    /**
     * Contains a list of all the characters that map one to one for UNICODE.
     */
    private static final String PLAIN_ASCII = 
              "AaEeIiOoUu"    // grave
            + "AaEeIiOoUuYy"  // acute
            + "AaEeIiOoUuYy"  // circumflex
            + "AaEeIiOoUuYy"  // tilde
            + "AaEeIiOoUuYy"  // umlaut
            + "Aa"            // ring
            + "Cc"            // cedilla
            + "Nn"            // n tilde (spanish)
            ;

    /**
     * Actual accented values, corresponds one to one with ASCII
     */
    private static final String UNICODE =
         "\u00C0\u00E0\u00C8\u00E8\u00CC\u00EC\u00D2\u00F2\u00D9\u00F9"             
        +"\u00C1\u00E1\u00C9\u00E9\u00CD\u00ED\u00D3\u00F3\u00DA\u00FA\u00DD\u00FD" 
        +"\u00C2\u00E2\u00CA\u00EA\u00CE\u00EE\u00D4\u00F4\u00DB\u00FB\u0176\u0177" 
        +"\u00C2\u00E2\u00CA\u00EA\u00CE\u00EE\u00D4\u00F4\u00DB\u00FB\u0176\u0177" 
        +"\u00C4\u00E4\u00CB\u00EB\u00CF\u00EF\u00D6\u00F6\u00DC\u00FC\u0178\u00FF" 
        +"\u00C5\u00E5"                                                             
        +"\u00C7\u00E7"  
        +"\u00D1\u00F1"
     ;

    // private constructor, can't be instanciated!
    private AsciiUtils() {      
    }


    /**
     * Removes accentued from a string and replace with ascii equivalent
     * @param s The string to englishify
     * @return The string without the french and spanish stuff.
     */
    public static String convertNonAscii(String s) {

        StringBuilder b = new StringBuilder();

        int n = s.length();
        for (int i = 0; i < n; i++) {
            char c = s.charAt(i);
            int pos = UNICODE.indexOf(c);
            if (pos > -1) {
              b.append(PLAIN_ASCII.charAt(pos));
            } else {
              b.append(c);
            }
        }

       return b.toString();

    }

}

Answer 3

URLEncoder 用 + 代替空格。 Don 发布的 Asccii 类不会删除空格，但下一个函数可用于该提案：

public static String removeSpaces(String s) {
    StringTokenizer st = new StringTokenizer(s," ",false);
    String t="";
    while (st.hasMoreElements()) t += st.nextElement();
        return t;
}

Answer 4

注意 Don 解决方案适用于代码中的字符串，但不适用于来自 UTF-8 编码文件的字符串

这是我最好的解决方案，使用 URLEncode 并在之后转义十六进制字符：

String s = "Cerepedia, una apliación web";
String ENCODING= "uft-8";
String encoded_s = URLEncoder.encode(s,ENCODING); // Cerepedia+una+aplicaci%C3%83%C2%B3n+web
String s_hexa_free = EncodingTableUtils.replaceHexa(,ENCODING)); //  Cerepedia+una+aplicacion+web

EncodingTableUtils

import java.util.HashMap;
import java.util.Iterator;
import java.util.Set;

public class EncodingTableUtils {
    public final static HashMap iso88591 = new HashMap();
    static {
        iso88591.put("%C3%A1", "a"); // á
        iso88591.put("%C3%81", "A"); // Á
        iso88591.put("%C3%A9", "e"); // é
        iso88591.put("%C3%89", "E"); // É
        iso88591.put("%C3%AD", "i"); // í
        iso88591.put("%C3%8D", "I"); // Í
        iso88591.put("%C3%93", "O"); // Ó
        iso88591.put("%C3%B3", "o"); // ó
        iso88591.put("%C3%BA", "u"); // ú
        iso88591.put("%C3%9A", "U"); // Ú
        iso88591.put("%C3%91", "N"); // Ñ
        iso88591.put("%C3%B1", "n"); // ñ
    }
    public final static HashMap utf8 = new HashMap();
    static {
        utf8.put("%C3%83%C2%A1", "a"); // á
        utf8.put("%C3%83%EF%BF", "A"); // Á
        utf8.put("%BD%C3%83%C2", "e"); // é
        utf8.put("%A9%C3%83%E2", "E"); // É
        utf8.put("%80%B0%C3%83", "i"); // í
        utf8.put("%C2%AD%C3%83", "I"); // Í
        utf8.put("%EF%BF%BD%C3", "O"); // Ó
        utf8.put("%C3%83%C2%B3", "o"); // ó
        utf8.put("%83%E2%80%9C", "u"); // ú     
        utf8.put("%C3%83%C2%BA", "U"); // Ú
        utf8.put("%C3%83%C5%A1", "N"); // Ñ
        utf8.put("%C3%83%E2%80", "n"); // ñ
    }

    public final static HashMap enc_table = new HashMap();
    static {
        enc_table.put("iso-8859-1", iso88591);
        enc_table.put("utf-8", utf8);
    }


    /**
     * Replace Hexadecimal characters with equivalent english not special ones
     * <p>Example: á Hexa: %C3%A1 gets replaced with a</p>
     * @param s Usually a string coming from URLEncode.encode
     * @param enc Encoding UTF-8 or ISO-8850-1
     */
    public static String convertHexaDecimal(String s, String enc) {
        HashMap characters = (HashMap) enc_table.get(enc.toLowerCase());
        if(characters==null) return "";
        Set keys = characters.keySet();
        Iterator it = keys.iterator();
        while(it.hasNext()) {
            String key = (String) it.next();
            String regex = EscapeChars.forRegex(key);
            String replacement = (String) characters.get(key); 
            s = s.replaceAll(regex, replacement);           
        }
        return s;
    }
}

EscapeChars 类

public final class EscapeChars {
/**
  * Replace characters having special meaning in regular expressions
  * with their escaped equivalents, preceded by a '\' character.
  *
  * <P>The escaped characters include :
  *<ul>
  *<li>.
  *<li>\
  *<li>?, * , and +
  *<li>&
  *<li>:
  *<li>{ and }
  *<li>[ and ]
  *<li>( and )
  *<li>^ and $
  *</ul>
  */
  public static String forRegex(String aRegexFragment){
    final StringBuilder result = new StringBuilder();

    final StringCharacterIterator iterator = new StringCharacterIterator(aRegexFragment);
    char character =  iterator.current();
    while (character != CharacterIterator.DONE ){
      /*
      * All literals need to have backslashes doubled.
      */
      if (character == '.') {
        result.append("\\.");
      }
      else if (character == '\\') {
        result.append("\\\\");
      }
      else if (character == '?') {
        result.append("\\?");
      }
      else if (character == '*') {
        result.append("\\*");
      }
      else if (character == '+') {
        result.append("\\+");
      }
      else if (character == '&') {
        result.append("\\&");
      }
      else if (character == ':') {
        result.append("\\:");
      }
      else if (character == '{') {
        result.append("\\{");
      }
      else if (character == '}') {
        result.append("\\}");
      }
      else if (character == '[') {
        result.append("\\[");
      }
      else if (character == ']') {
        result.append("\\]");
      }
      else if (character == '(') {
        result.append("\\(");
      }
      else if (character == ')') {
        result.append("\\)");
      }
      else if (character == '^') {
        result.append("\\^");
      }
      else if (character == '$') {
        result.append("\\$");
      }
      else {
        //the char is not a special one
        //add it to the result as is
        result.append(character);
      }
      character = iterator.next();
    }
    return result.toString();
  }
}

Answer 5

试试这个代码

 public class Test {

    public static void main(final String[] args) {
        String str = "Cerepedia, una apliación web";
        String[] parts = str.split(" ");
        int sum=0;
        for (int i=0;i<=parts.length-1;i++) {
            sum = sum+parts[i].length();
        }

        int k=0;
        char[] url = new char[25];
        for (int i=0;i<=parts.length-1;i++) {
             char[] temp = parts[i].toCharArray();


             for(int j=0;j<temp.length;j++){

                 url[k]=temp[j];
                 k++;
             }

        }
        System.out.println(url);

    }
}