1. When the java.util.list add object, it is put the address of the object and does not generate a new object.
2, Java does not have the basic data type of the unsigned byte. The bytes of more than 127 or more are treated as a negative number, conversion as follows:
INT unsignedbyte = address [i] <0? address [i] 256: address [i];
3, the difference between SET and LIST, the elements containing the SET will not be repeated, which is disordered.
