Buffer的几个属性和方法速记

 

java.nio.Buffer 

 

属性

 

mark   position
limit 一般情况下limit==catacity capacity 此属性一经设置，就不会改变 remaing limit-position address  

 

查询类方法

 

remaining	limit - position;
hasRemaining	limit < position;

 

改变类方法

 

mark	mark=position;
reset	position=mark;
clear	position=0; limit=capacity; mark=-1;
flip	limit=position; position=0; mark=-1;
rewind	position=0; mark=-1;
limit()	limit=newLimit;   if (position > limit) position = limit; if (mark > limit) mark = -1;
position()	position = newPosition;   if (mark > position) mark = -1;

 

System.arraycopy(hb, ix(position()), hb, ix(0), remaining());

 

position(remaining());

limit(capacity());

 

compact
slice	new HeapIntBuffer(hb, -1, 0, this.remaining(), this.remaining(), this.position() + offset);   共享底层存储byte[] mark=-1; position=0; limit=remaining; capacity=remaing; offset = offset+position;
duplicate	new HeapByteBuffer(hb,   this.markValue(), this.position(), this.limit(), this.capacity(), offset);   共享底层存储byte[] mark=mark; position=position; limit=limit; capacity=capacity; offset = offset;