Android Base64Encoder解决方案

原文链接： https://blog.csdn.net/sxsj333/article/details/42641063

public class Base64Encoder {private static final char last2byte = (char) Integer.parseInt("00000011", 2);private static final char last4byte = (char) Integer.parseInt("00001111", 2);private static final char last6byte = (char) Integer.parseInt("00111111", 2);private static final char lead6byte = (char) Integer.parseInt("11111100", 2);private static final char lead4byte = (char) Integer.parseInt("11110000", 2);private static final char lead2byte = (char) Integer.parseInt("11000000", 2);private static final char[] encodeTable = new char[] { 'A', 'B', 'C', 'D','E', 'F', 'G', 'H', 'I', 'J', 'K', 'L', 'M', 'N', 'O', 'P', 'Q','R', 'S', 'T', 'U', 'V', 'W', 'X', 'Y', 'Z', 'a', 'b', 'c', 'd','e', 'f', 'g', 'h', 'i', 'j', 'k', 'l', 'm', 'n', 'o', 'p', 'q','r', 's', 't', 'u', 'v', 'w', 'x', 'y', 'z', '0', '1', '2', '3','4', '5', '6', '7', '8', '9', '+', '/' }; /** * Base64 encoding. *  * @param from *            The src data. * @return */public static String encode(byte[] from) {StringBuffer to = new StringBuffer((int) (from.length * 1.34) + 3);int num = 0;char currentByte = 0;for (int i = 0; i < from.length; i++) {num = num % 8;while (num < 8) {switch (num) {case 0:currentByte = (char) (from[i] & lead6byte);currentByte = (char) (currentByte >>> 2);break;case 2:currentByte = (char) (from[i] & last6byte);break;case 4:currentByte = (char) (from[i] & last4byte);currentByte = (char) (currentByte << 2);if ((i + 1) < from.length) {currentByte |= (from[i + 1] & lead2byte) >>> 6;}break;case 6:currentByte = (char) (from[i] & last2byte);currentByte = (char) (currentByte << 4);if ((i + 1) < from.length) {currentByte |= (from[i + 1] & lead4byte) >>> 4;}break;}to.append(encodeTable[currentByte]);num += 6;}}if (to.length() % 4 != 0) {for (int i = 4 - to.length() % 4; i > 0; i--) {to.append("=");}}return to.toString();}}

非常感谢：参天大树SJ

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