1.在阅读源码的时候经常发现有一些标志属性使用一些位操作来判断是否具有该标志,增加标志或者去除标志. 比如View.java中的 /** * This view does not want keystrokes. Use with TAKES_FOCUS_MASK when * calling setFlags. */ private static final int NOT_FOCUSABLE = 0x00000000; /** * This view wants keystrokes. Us
public final static char[] BToA = "0123456789abcdef".toCharArray() ; 1.16进制字符串转为字节数组 /** * 把16进制字符串转换成字节数组 * @param hex * @return */ public static byte[] hexStringToByte(String hex) { int len = (hex.length() / 2); byte[] result = new byte[len];