### Question:
BitUtil { public static String int2Bin(int source) { return Integer.toBinaryString(source); }  static String int2Bin(int source); static int bin2Int(String source); static String long2Bin(long source); static long bin2Long(String source); static boolean getIntBit(int source, int pos); static int setIntBit(int source, int pos, boolean value); static boolean getLongBit(long source, int pos); static long setLongBit(long source, int pos, boolean value);  }### Answer:
@Test public void int2Bin() { assertEquals("111_1111_1111_1111_1111_1111_1111_1111".replace("_", ""), BitUtil.int2Bin(2147483647)); }