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25 
26 package sun.nio.ch;
27 
28 /**
29  * Manipulates a native array of pollfd structs.
30  *
31  * @author Mike McCloskey
32  * @since 1.4
33  */
34 
35 public abstract class AbstractPollArrayWrapper {
36 
37     // Miscellaneous constants
38     static final short SIZE_POLLFD   = 8;
39     static final short FD_OFFSET     = 0;
40     static final short EVENT_OFFSET  = 4;
41     static final short REVENT_OFFSET = 6;
42 
43     // The poll fd array
44     protected AllocatedNativeObject pollArray;
45 
46     // Number of valid entries in the pollArray
47     protected int totalChannels = 0;
48 
49     // Base address of the native pollArray
50     protected long pollArrayAddress;
51 
52     // Access methods for fd structures
getEventOps(int i)53     int getEventOps(int i) {
54         int offset = SIZE_POLLFD * i + EVENT_OFFSET;
55         return pollArray.getShort(offset);
56     }
57 
getReventOps(int i)58     int getReventOps(int i) {
59         int offset = SIZE_POLLFD * i + REVENT_OFFSET;
60         return pollArray.getShort(offset);
61     }
62 
getDescriptor(int i)63     int getDescriptor(int i) {
64         int offset = SIZE_POLLFD * i + FD_OFFSET;
65         return pollArray.getInt(offset);
66     }
67 
putEventOps(int i, int event)68     void putEventOps(int i, int event) {
69         int offset = SIZE_POLLFD * i + EVENT_OFFSET;
70         pollArray.putShort(offset, (short)event);
71     }
72 
putReventOps(int i, int revent)73     void putReventOps(int i, int revent) {
74         int offset = SIZE_POLLFD * i + REVENT_OFFSET;
75         pollArray.putShort(offset, (short)revent);
76     }
77 
putDescriptor(int i, int fd)78     void putDescriptor(int i, int fd) {
79         int offset = SIZE_POLLFD * i + FD_OFFSET;
80         pollArray.putInt(offset, fd);
81     }
82 
83 }
84