Java String Unescape unescape(String str, char escapeChar, char[] targetChars, char[] escapedChars)

Description

unescape

License

MIT License

Declaration

public static String unescape(String str, char escapeChar, char[] targetChars, char[] escapedChars) 

Method Source Code

//package com.java2s;
/*!// ww  w  . jav a 2s . c  o  m
 * mifmi-commons4j
 * https://github.com/mifmi/mifmi-commons4j
 *
 * Copyright (c) 2015 mifmi.org and other contributors
 * Released under the MIT license
 * https://opensource.org/licenses/MIT
 */

public class Main {
    public static String unescape(String str, char escapeChar, char[] targetChars, char[] escapedChars) {
        return unescape(str, escapeChar, targetChars, escapedChars, false);
    }

    public static String unescape(String str, char escapeChar, char[] targetChars, char[] escapedChars,
            boolean useUnicodeEscape) {
        if (str == null) {
            return null;
        }

        int len = str.length();
        StringBuilder sb = new StringBuilder(len);
        unescape(sb, str, escapeChar, targetChars, escapedChars, useUnicodeEscape);
        return sb.toString();
    }

    public static void unescape(StringBuilder sb, String str, char escapeChar, char[] targetChars,
            char[] escapedChars) {
        unescape(sb, str, escapeChar, targetChars, escapedChars, false);
    }

    public static void unescape(StringBuilder sb, String str, char escapeChar, char[] targetChars,
            char[] escapedChars, boolean useUnicodeEscape) {
        if (targetChars != null && escapedChars != null) {
            if (targetChars.length != escapedChars.length) {
                throw new IllegalArgumentException();
            }
        }

        if (str == null) {
            return;
        }

        int idx = str.indexOf(escapeChar);
        if (idx == -1) {
            sb.append(str);
            return;
        }

        int len = str.length();
        boolean escape = false;
        for (int i = 0; i < len; i++) {
            char ch = str.charAt(i);
            if (ch == escapeChar) {
                if (escape) {
                    sb.append(escapeChar);
                    escape = false;
                } else {
                    escape = true;
                }
            } else {
                if (escape) {
                    int targetIdx = -1;
                    if (escapedChars != null) {
                        for (int j = 0; j < escapedChars.length; j++) {
                            if (ch == escapedChars[j]) {
                                targetIdx = j;
                                break;
                            }
                        }
                    }
                    if (targetIdx == -1) {
                        if (useUnicodeEscape && ch == 'u') {
                            i++;
                            String codePointHexStr = str.substring(i, Math.min(i + 4, len));
                            i += 3;
                            try {
                                sb.append((char) Integer.parseInt(codePointHexStr, 16));
                            } catch (NumberFormatException e) {
                                // parse failed
                                sb.append('u');
                                sb.append(codePointHexStr);
                            }
                        } else if (useUnicodeEscape && ch == 'U') {
                            i++;
                            String codePointHexStr = str.substring(i, Math.min(i + 8, len));
                            i += 7;
                            try {
                                int codePoint = (int) Long.parseLong(codePointHexStr, 16);
                                sb.appendCodePoint(codePoint);
                            } catch (IllegalArgumentException e) {
                                // parse failed
                                sb.append('U');
                                sb.append(codePointHexStr);
                            }
                        } else {
                            sb.append(ch);
                        }
                    } else {
                        if (targetChars == null) {
                            sb.append(ch);
                        } else {
                            sb.append(targetChars[targetIdx]);
                        }
                    }
                    escape = false;
                } else {
                    sb.append(ch);
                }
            }
        }
    }

    public static String toString(StringBuilder sb, boolean trim) {
        if (sb == null) {
            return null;
        }

        if (!trim) {
            return sb.toString();
        }

        int len = sb.length();
        if (len == 0) {
            return "";
        }

        int sIdx;
        for (sIdx = 0; sIdx < len; sIdx++) {
            char ch = sb.charAt(sIdx);
            if (!Character.isWhitespace(ch)) {
                break;
            }
        }

        if (sIdx == len) {
            return "";
        }

        int eIdx;
        for (eIdx = len - 1; 0 <= eIdx; eIdx--) {
            char ch = sb.charAt(eIdx);
            if (!Character.isWhitespace(ch)) {
                break;
            }
        }

        return sb.substring(sIdx, eIdx + 1);
    }

    public static int indexOf(CharSequence charSeq, char ch) {
        return indexOf(charSeq, ch, 0);
    }

    public static int indexOf(CharSequence charSeq, char ch, int fromIndex) {
        if (charSeq == null) {
            return -1;
        }
        int len = charSeq.length();
        for (int i = fromIndex; i < len; i++) {
            char c = charSeq.charAt(i);
            if (c == ch) {
                return i;
            }
        }
        return -1;
    }

    public static int indexOf(CharSequence charSeq, char[] ch) {
        return indexOf(charSeq, ch, 0);
    }

    public static int indexOf(CharSequence charSeq, char[] ch, int fromIndex) {
        if (charSeq == null) {
            return -1;
        }
        int len = charSeq.length();
        for (int i = fromIndex; i < len; i++) {
            char c = charSeq.charAt(i);
            for (int j = 0; j < ch.length; j++) {
                if (c == ch[j]) {
                    return i;
                }
            }
        }
        return -1;
    }
}

Related

1. unescape(String str)
2. unescape(String str)
3. unescape(String str)
4. unescape(String str)
5. unescape(String str)
6. unescape(String string)
7. unescape(String string)
8. unescape(String string)
9. unescape(String string)