Method toString

src/main/com/bfo/zeroconf/Stringify.java:135–202

A quick single-method JSON writer, intended to write Maps/Lists/Strings/Numbers/Booleans

(Object o)

     * A quick single-method JSON writer, intended to write Maps/Lists/Strings/Numbers/Booleans
     */
    static String toString(Object o) {
        if (o == null) {
            return null;
        } else if (o instanceof CharSequence) {
            CharSequence s = (CharSequence)o;
            StringBuilder sb = new StringBuilder();
            sb.append('"');
            for (int i=0;i<s.length();i++) {
                char c = s.charAt(i);
                if (c == '\n') {
                    sb.append("\\n");
                } else if (c == '\r') {
                    sb.append("\\r");
                } else if (c == '\t') {
                    sb.append("\\t");
                } else if (c == '"') {
                    sb.append("\\\"");
                } else if (c == '\\') {
                    sb.append("\\\\");
                } else if (Character.isISOControl(c)) {     // 0x00-0x1F, 0x80-0x9F
                    String t = Integer.toHexString(c);
                    sb.append("\\u");
                    for (int j=t.length();j<4;j++) {
                        sb.append('0');
                    }
                    sb.append(t);
                } else {
                    sb.append(c);
                }
            }
            sb.append('"');
            return sb.toString();
        } else if (o instanceof Map) {
            Map<?,?> m = (Map<?,?>)o;
            StringBuilder sb = new StringBuilder();
            sb.append('{');
            boolean first = true;
            for (Map.Entry<?,?> e : m.entrySet()) {
                if (!first) {
                    sb.append(',');
                }
                sb.append(toString((String)e.getKey()));
                sb.append(':');
                sb.append(toString(e.getValue()));
                first = false;
            }
            sb.append('}');
            return sb.toString();
        } else if (o instanceof List) {
            List<?> l = (List<?>)o;
            StringBuilder sb = new StringBuilder();
            sb.append('[');
            boolean first = true;
            for (Object p : l) {
                if (!first) {
                    sb.append(',');
                }
                sb.append(toString(p));