Java String Quote quote(String value)

Description

Quote the given string; single quotes are escaped.

License

Apache License

Parameter

Parameter	Description
value	The value to quote.

Return

The quoted string.

Declaration

public static String quote(String value) 

Method Source Code

//package com.java2s;
/*//from   www .  j  a va  2 s . c o  m
 *      Copyright (C) 2012-2015 DataStax Inc.
 *
 *   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 {
    /**
     * Quote the given string; single quotes are escaped.
     * If the given string is null, this method returns a quoted empty string ({@code ''}).
     *
     * @param value The value to quote.
     * @return The quoted string.
     */
    public static String quote(String value) {
        return quote(value, '\'');
    }

    /**
     * Quotes text and escapes any existing quotes in the text.
     * {@code String.replace()} is a bit too inefficient (see JAVA-67, JAVA-1262).
     *
     * @param text      The text.
     * @param quoteChar The character to use as a quote.
     * @return The text with surrounded in quotes with all existing quotes escaped with (i.e. ' becomes '')
     */
    private static String quote(String text, char quoteChar) {
        if (text == null || text.isEmpty())
            return emptyQuoted(quoteChar);

        int nbMatch = 0;
        int start = -1;
        do {
            start = text.indexOf(quoteChar, start + 1);
            if (start != -1)
                ++nbMatch;
        } while (start != -1);

        // no quotes found that need to be escaped, simply surround in quotes and return.
        if (nbMatch == 0)
            return quoteChar + text + quoteChar;

        // 2 for beginning and end quotes.
        // length for original text
        // nbMatch for escape characters to add to quotes to be escaped.
        int newLength = 2 + text.length() + nbMatch;
        char[] result = new char[newLength];
        result[0] = quoteChar;
        result[newLength - 1] = quoteChar;
        int newIdx = 1;
        for (int i = 0; i < text.length(); i++) {
            char c = text.charAt(i);
            if (c == quoteChar) {
                // escape quote with another occurrence.
                result[newIdx++] = c;
                result[newIdx++] = c;
            } else {
                result[newIdx++] = c;
            }
        }
        return new String(result);
    }

    /**
     * @param quoteChar " or '
     * @return A quoted empty string.
     */
    private static String emptyQuoted(char quoteChar) {
        // don't handle non quote characters, this is done so that these are interned and don't create
        // repeated empty quoted strings.
        assert quoteChar == '"' || quoteChar == '\'';
        if (quoteChar == '"')
            return "\"\"";
        else
            return "''";
    }
}

Related

1. quote(String val)
2. quote(String val, char quote)
3. quote(String value)
4. quote(String value)
5. quote(String value)
6. quote(StringBuilder buf, String str)
7. quote(StringBuilder sb, String str)
8. quote4CMDLine(String str)
9. quoteAndClean(String str)