Java String Quote quote(CharSequence cs)

Description

Quotes the given string as Java string literal style, and returns it.

License

Apache License

Parameter

Parameter	Description
cs	the source string

Return

the quoted string

Declaration

public static String quote(CharSequence cs) 

Method Source Code

//package com.java2s;
/**/*from   www  . jav a2  s . c  om*/
 * Copyright 2011-2017 Asakusa Framework Team.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

public class Main {
    private static final char[] ASCII_SPECIAL_ESCAPE = new char[128];

    /**
     * Quotes the given string as Java string literal style, and returns it.
     * @param cs the source string
     * @return the quoted string
     */
    public static String quote(CharSequence cs) {
        StringBuilder buf = new StringBuilder();
        quoteTo(cs, buf);
        return buf.toString();
    }

    /**
     * Quotes the given string as Java string literal style, and puts it into the given buffer.
     * @param cs the source string
     * @param target the destination buffer
     */
    public static void quoteTo(CharSequence cs, StringBuilder target) {
        target.append('"');
        for (int i = 0, n = cs.length(); i < n; i++) {
            char c = cs.charAt(i);
            if (c <= 0x7f && ASCII_SPECIAL_ESCAPE[c] != 0) {
                target.append('\\');
                target.append(ASCII_SPECIAL_ESCAPE[c]);
            } else if (Character.isISOControl(c) || Character.isDefined(c) == false
                    || Character.isLowSurrogate(c)) {
                target.append(String.format("\\u%04x", (int) c)); //$NON-NLS-1$
            } else if (Character.isHighSurrogate(c)) {
                if (i + 1 < n) {
                    char next = cs.charAt(i + 1);
                    if (Character.isLowSurrogate(next)) {
                        target.append(c);
                        target.append(next);
                        i++;
                        continue;
                    }
                }
                target.append(String.format("\\u%04x", (int) c)); //$NON-NLS-1$
            } else {
                target.append(c);
            }
        }
        target.append('"');
    }

    private static String toString(CharSequence cs, int offset, int length) {
        if (offset == 0 && length == cs.length()) {
            return cs.toString();
        }
        return cs.subSequence(offset, offset + length).toString();
    }
}

Related

1. quote(CharSequence str)
2. quote(CharSequence value)
3. quote(final CharSequence original)
4. quote(final CharSequence phrase)