Java String Encode encodeToString(String s)

Description

encode To String

License

Open Source License

Declaration

public static String encodeToString(String s) 

Method Source Code

//package com.java2s;
/**/* w  w w  . j  a  v  a 2  s . c  o  m*/
 * Copyright 2013-2014 Guoqiang Chen, Shanghai, China. All rights reserved.
 *
 *   Author: Guoqiang Chen
 *    Email: subchen@gmail.com
 *   WebURL: https://github.com/subchen
 *
 * 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.
 */

import java.io.UnsupportedEncodingException;

public class Main {
    private static final char[] CHARS = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/"
            .toCharArray();
    private static final String ENCODING = "UTF-8";

    public static String encodeToString(String s) {
        try {
            return new String(encodeToChar(s.getBytes(ENCODING), false));
        } catch (UnsupportedEncodingException ignore) {
            return null;
        }
    }

    public static String encodeToString(String s, boolean lineSep) {
        try {
            return new String(encodeToChar(s.getBytes(ENCODING), lineSep));
        } catch (UnsupportedEncodingException ignore) {
            return null;
        }
    }

    public static String encodeToString(byte[] arr) {
        return new String(encodeToChar(arr, false));
    }

    /**
     * Encodes a raw byte array into a BASE64 <code>String</code>.
     */
    public static String encodeToString(byte[] arr, boolean lineSep) {
        return new String(encodeToChar(arr, lineSep));
    }

    /**
     * Encodes a raw byte array into a BASE64 <code>char[]</code>.
     * @param lineSeparator optional CRLF after 76 chars, unless EOF.
     */
    public static char[] encodeToChar(byte[] arr, boolean lineSeparator) {
        int len = arr != null ? arr.length : 0;
        if (len == 0) {
            return new char[0];
        }

        int evenlen = (len / 3) * 3;
        int cnt = ((len - 1) / 3 + 1) << 2;
        int destLen = cnt + (lineSeparator ? (cnt - 1) / 76 << 1 : 0);
        char[] dest = new char[destLen];

        for (int s = 0, d = 0, cc = 0; s < evenlen;) {
            int i = (arr[s++] & 0xff) << 16 | (arr[s++] & 0xff) << 8 | (arr[s++] & 0xff);

            dest[d++] = CHARS[(i >>> 18) & 0x3f];
            dest[d++] = CHARS[(i >>> 12) & 0x3f];
            dest[d++] = CHARS[(i >>> 6) & 0x3f];
            dest[d++] = CHARS[i & 0x3f];

            if (lineSeparator && (++cc == 19) && (d < (destLen - 2))) {
                dest[d++] = '\r';
                dest[d++] = '\n';
                cc = 0;
            }
        }

        int left = len - evenlen; // 0 - 2.
        if (left > 0) {
            int i = ((arr[evenlen] & 0xff) << 10) | (left == 2 ? ((arr[len - 1] & 0xff) << 2) : 0);

            dest[destLen - 4] = CHARS[i >> 12];
            dest[destLen - 3] = CHARS[(i >>> 6) & 0x3f];
            dest[destLen - 2] = left == 2 ? CHARS[i & 0x3f] : '=';
            dest[destLen - 1] = '=';
        }
        return dest;
    }
}

Related

1. encodeTexts(String s)
2. encodeTextValue(char[] characters, int offset, int length, Writer writer)
3. encodeThoroughly(String s)
4. encodeToFlex(Object o)
5. encodeToForm(Map msg)
6. encodeURNComponent(String value)
7. encodeUTF8(String input, boolean keepSpaces)
8. encodeUTF8(String s)
9. encodeUTF8(String s)