java常用方法(String)7

  /**
     * Creates a Map from an encoded name/value pair string
     * @param str The string to decode and format
     * @param trim Trim whitespace off fields
     * @return a Map of name/value pairs
     */
    public static Map strToMap(String str, boolean trim) {
        if (str == null) return null;
        Map decodedMap = new HashMap();
        List elements = split(str, "|");
        Iterator i = elements.iterator();

        while (i.hasNext()) {
            String s = (String) i.next();
            List e = split(s, "=");

            if (e.size() != 2) {
                continue;
            }
            String name = (String) e.get(0);
            String value = (String) e.get(1);
            if (trim) {
                if (name != null) {
                    name = name.trim();
                }
                if (value != null) {
                    value = value.trim();
                }
            }

            try {
                decodedMap.put(URLDecoder.decode(name, "UTF-8"), URLDecoder.decode(value, "UTF-8"));
            } catch (UnsupportedEncodingException e1) {
            }
        }
        return decodedMap;
    }

    /**
     * Creates a Map from an encoded name/value pair string
     * @param str The string to decode and format
     * @return a Map of name/value pairs
     */
    public static Map strToMap(String str) {
        return strToMap(str, false);
    }

    /**
     * Creates an encoded String from a Map of name/value pairs (MUST BE STRINGS!)
     * @param map The Map of name/value pairs
     * @return String The encoded String
     */
    public static String mapToStr(Map map) {
        if (map == null) return null;
        StringBuffer buf = new StringBuffer();
        Set keySet = map.keySet();
        Iterator i = keySet.iterator();
        boolean first = true;

        while (i.hasNext()) {
            Object key = i.next();
            Object value = map.get(key);

            if (!(key instanceof String) || !(value instanceof String))
                continue;
            String encodedName = null;
            try {
                encodedName = URLEncoder.encode((String) key, "UTF-8");
            } catch (UnsupportedEncodingException e) {
            }
            String encodedValue = null;
            try {
                encodedValue = URLEncoder.encode((String) value, "UTF-8");
            } catch (UnsupportedEncodingException e) {
            }

            if (first)
                first = false;
            else
                buf.append("|");

            buf.append(encodedName);
            buf.append("=");
            buf.append(encodedValue);
        }
        return buf.toString();
    }

    /**
     * Create a Map from a List of keys and a List of values
     * @param keys List of keys
     * @param values List of values
     * @return Map of combined lists
     * @throws IllegalArgumentException When either List is null or the sizes do not equal
     */
    public static Map createMap(List keys, List values) {
        if (keys == null || values == null || keys.size() != values.size()) {
            throw new IllegalArgumentException("Keys and Values cannot be null and must be the same size");
        }
        Map newMap = new HashMap();
        for (int i = 0; i < keys.size(); i++) {
            newMap.put(keys.get(i), values.get(i));
        }
        return newMap;
    }

    /** Make sure the string starts with a forward slash but does not end with one; converts back-slashes to forward-slashes; if in String is null or empty, returns zero length string. */
    public static String cleanUpPathPrefix(String prefix) {
        if (prefix == null || prefix.length() == 0) return "";

        StringBuffer cppBuff = new StringBuffer(prefix.replace('\\', '/'));

        if (cppBuff.charAt(0) != '/') {
            cppBuff.insert(0, '/');
        }
        if (cppBuff.charAt(cppBuff.length() - 1) == '/') {
            cppBuff.deleteCharAt(cppBuff.length() - 1);
        }
        return cppBuff.toString();
    }