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25 
26 package sun.nio.ch;
27 
28 import sun.misc.*;
29 
30 
31 /**
32  * Manipulates a native array of pollfd structs.
33  *
34  * @author Mike McCloskey
35  * @since 1.4
36  */
37 
38 abstract class AbstractPollArrayWrapper {
39 
40     // Event masks
41     static final short POLLIN       = 0x0001;
42     static final short POLLOUT      = 0x0004;
43     static final short POLLERR      = 0x0008;
44     static final short POLLHUP      = 0x0010;
45     static final short POLLNVAL     = 0x0020;
46     static final short POLLREMOVE   = 0x0800;
47 
48     // Miscellaneous constants
49     static final short SIZE_POLLFD   = 8;
50     static final short FD_OFFSET     = 0;
51     static final short EVENT_OFFSET  = 4;
52     static final short REVENT_OFFSET = 6;
53 
54     // The poll fd array
55     protected AllocatedNativeObject pollArray;
56 
57     // Number of valid entries in the pollArray
58     protected int totalChannels = 0;
59 
60     // Base address of the native pollArray
61     protected long pollArrayAddress;
62 
63     // Access methods for fd structures
getEventOps(int i)64     int getEventOps(int i) {
65         int offset = SIZE_POLLFD * i + EVENT_OFFSET;
66         return pollArray.getShort(offset);
67     }
68 
getReventOps(int i)69     int getReventOps(int i) {
70         int offset = SIZE_POLLFD * i + REVENT_OFFSET;
71         return pollArray.getShort(offset);
72     }
73 
getDescriptor(int i)74     int getDescriptor(int i) {
75         int offset = SIZE_POLLFD * i + FD_OFFSET;
76         return pollArray.getInt(offset);
77     }
78 
putEventOps(int i, int event)79     void putEventOps(int i, int event) {
80         int offset = SIZE_POLLFD * i + EVENT_OFFSET;
81         pollArray.putShort(offset, (short)event);
82     }
83 
putReventOps(int i, int revent)84     void putReventOps(int i, int revent) {
85         int offset = SIZE_POLLFD * i + REVENT_OFFSET;
86         pollArray.putShort(offset, (short)revent);
87     }
88 
putDescriptor(int i, int fd)89     void putDescriptor(int i, int fd) {
90         int offset = SIZE_POLLFD * i + FD_OFFSET;
91         pollArray.putInt(offset, fd);
92     }
93 
94 }
95