Java執行緒同步問題synchronized

android usb 讀寫以前都是一讀一寫，但有些機器會出問題。就採用讀寫非同步的方法。

使用物件鎖，object自帶的，然後使用object的方法wait和notify/notifyall

使用方法簡單，記錄下

public synchronized int lra_setregister(int index,int address, int value) ;

mcmdnow = 0x53;
cmd[5] = (byte)index;
cmd[6] = (byte)(address);
cmd[7] = (byte)(value);
byte cmd4send = crc16.data4send(cmd);
writeusbserial(cmd4send,cmd4send.length);
synchronized (syncobject) catch (interruptedexception e) 
ret = mregistersetvalue;
}return ret;
}/**
* read register value by address
* @param address of registers need to read
* @return data in register
*/public synchronized int lra_getregister(int index,int address) ;
mcmdnow = 0x54;
cmd[5] = (byte)index;
cmd[6] = (byte)(address);
byte cmd4send = crc16.data4send(cmd);
writeusbserial(cmd4send,cmd4send.length);
synchronized (syncobject) catch (interruptedexception e) 
ret = mregisterreadvalue;
}return ret;
}public byte lra_getdeviceid() ;
mcmdnow = (byte) 0xff;
writeusbserial(cmd,cmd.length);
synchronized (syncobject) catch (interruptedexception e) 
}return mdeviceid;
}private boolean musbreadswitch = false;
private int musbreaddatalen = 20;
private byte musbreaddata = new byte[musbreaddatalen];
private byte musbreaddataclean = new byte[musbreaddatalen];
private byte mcmdnow = 0x00;
private object syncobject = new object();
//values return
private byte mdeviceid = new byte[13];
private byte mregisterreadvalue = 0x00;
private byte mregistersetvalue = 0x00;
class usbreadthread extends thread}}
}public byte ge***eviceid()
private int readreturndatafromusb(byte cmd, byte dataread)
break;
case 0x54:
mregisterreadvalue = dataread[5];
// mlistener.oneventcome(event.event_register_read_result_ok,mregisterreadvalue);
synchronized (syncobject) 
break;
case (byte) 0xff:
system.arraycopy(dataread,4,mdeviceid,0,13);
showdatadetail(mdeviceid,"readreturndatafromusb");
// mlistener.oneventcome(event.event_deviceid_read_result,ret);
synchronized (syncobject) 
break;
default:
break;
}}else
}else if((dataread[0] == 0x00) && (dataread[1] == 0x00) && (dataread[2] == 0x00) && (dataread[3] == 0x00) && (dataread[4] == 0x00)
&& (dataread[5] == 0x00))
}return ret;
}

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