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// 8-bit byte value byte b = (byte) 0b10000001; // 16-bit short value short s = (short) 0b1000000110000001; // 32-bit int value int i = 0b10100001010001011010000101000101; int j = 0B1000; // 64-bit long value with the L suffix long x = 0b00101100110101101011011011001001011101001010L;

有的時候，數字用二進位法來表示，會比八或十六進位來得清楚和易讀。舉例來說：

// Before private static byte[] unmask = { (byte) 0xFE, (byte) 0xFD, (byte) 0xFB, (byte) 0xF7, (byte) 0xEF, (byte) 0xDF, (byte) 0xBF, (byte) 0x7F }; // After private static byte[] unmask = { (byte) 0b11111110, (byte) 0b11111101, (byte) 0b11111011, (byte) 0b11110111, (byte) 0b11101111, (byte) 0b11011111, (byte) 0b10111111, (byte) 0b01111111 };

原本在 Java 語言中可以使用整數數字的地方，都可以用二進位表示法：

if ((flag & 0b00001111) >= 0b00000001) { switch (b) { case 0b00000011: return “foo”; case 0b10101001: return “bar”; } }

你也可以用它來設計迷宮陣列，或是點陣圖形的表情符號，像是下面這個笑臉圖：

public static final short[] HAPPY_FACE = { (short)0b0000011111100000; (short)0b0000100000010000; (short)0b0001000000001000; (short)0b0010000000000100; (short)0b0100000000000010; (short)0b1000011001100001; (short)0b1000011001100001; (short)0b1000000000000001; (short)0b1000000000000001; (short)0b1001000000001001; (short)0b1000100000010001; (short)0b0100011111100010; (short)0b0010000000000100; (short)0b0001000000001000; (short)0b0000100000010000; (short)0b0000011111100000; }