| 1 | package org.dcache.cells; |
| 2 | |
| 3 | import java.io.PrintWriter; |
| 4 | import java.util.Map; |
| 5 | |
| 6 | import dmg.util.Args; |
| 7 | import dmg.cells.nucleus.CellEndpoint; |
| 8 | import dmg.cells.nucleus.CellInfo; |
| 9 | import dmg.cells.nucleus.CellMessage; |
| 10 | import dmg.cells.nucleus.NoRouteToCellException; |
| 11 | import dmg.cells.nucleus.CellMessageAnswerable; |
| 12 | import dmg.cells.nucleus.SerializationException; |
| 13 | |
| 14 | public class AbstractCellComponent |
| 15 | implements CellInfoProvider, |
| 16 | CellSetupProvider, |
| 17 | CellMessageSender, |
| 18 | CellLifeCycleAware |
| 19 | { |
| 20 | private CellEndpoint _endpoint; |
| 21 | |
| 22 | /** |
| 23 | * Implements CellInfoProvider interface. |
| 24 | */ |
| 25 | public void getInfo(PrintWriter pw) {} |
| 26 | |
| 27 | /** |
| 28 | * Implements CellInfoProvider interface. |
| 29 | */ |
| 30 | public CellInfo getCellInfo(CellInfo info) |
| 31 | { |
| 32 | return info; |
| 33 | } |
| 34 | |
| 35 | /** |
| 36 | * Implements CellSetupProvider interface. |
| 37 | */ |
| 38 | public void printSetup(PrintWriter pw) {} |
| 39 | |
| 40 | /** |
| 41 | * Implements CellSetupProvider interface. |
| 42 | */ |
| 43 | public void beforeSetup() {} |
| 44 | |
| 45 | /** |
| 46 | * Implements CellSetupProvider interface. |
| 47 | */ |
| 48 | public void afterSetup() {} |
| 49 | |
| 50 | /** |
| 51 | * Implements CellLifeCycleAware interface. |
| 52 | */ |
| 53 | public void afterStart() {} |
| 54 | |
| 55 | /** |
| 56 | * Implements CellLifeCycleAware interface. |
| 57 | */ |
| 58 | public void beforeStop() {} |
| 59 | |
| 60 | /** |
| 61 | * Implements CellMessageSender interface. |
| 62 | */ |
| 63 | public void setCellEndpoint(CellEndpoint endpoint) |
| 64 | { |
| 65 | _endpoint = endpoint; |
| 66 | } |
| 67 | |
| 68 | /** |
| 69 | * Implements CellMessageSender interface. |
| 70 | */ |
| 71 | protected CellEndpoint getCellEndpoint() |
| 72 | { |
| 73 | return _endpoint; |
| 74 | } |
| 75 | |
| 76 | /** |
| 77 | * Sends <code>envelope</code>. |
| 78 | * |
| 79 | * @param envelope the cell message to be sent. |
| 80 | * @throws SerializationException if the payload object of this |
| 81 | * message is not serializable. |
| 82 | * @throws NoRouteToCellException if the destination could not be |
| 83 | * reached. |
| 84 | */ |
| 85 | protected void sendMessage(CellMessage envelope) |
| 86 | throws SerializationException, |
| 87 | NoRouteToCellException |
| 88 | { |
| 89 | _endpoint.sendMessage(envelope); |
| 90 | } |
| 91 | |
| 92 | /** |
| 93 | * Sends <code>envelope</code>. The <code>callback</code> argument |
| 94 | * (which has to be non-null) allows to specify an object which is |
| 95 | * informed as soon as an has answer arrived or if the timeout has |
| 96 | * expired. |
| 97 | * |
| 98 | * @param envelope the cell message to be sent. |
| 99 | * @param callback specifies an object class which will be informed |
| 100 | * as soon as the message arrives. |
| 101 | * @param timeout is the timeout in msec. |
| 102 | * @exception SerializationException if the payload object of this |
| 103 | * message is not serializable. |
| 104 | */ |
| 105 | protected void sendMessage(CellMessage envelope, |
| 106 | CellMessageAnswerable callback, |
| 107 | long timeout) |
| 108 | throws SerializationException |
| 109 | { |
| 110 | _endpoint.sendMessage(envelope, callback, timeout); |
| 111 | } |
| 112 | |
| 113 | /** |
| 114 | * Sends <code>envelope</code> and waits <code>timeout</code> |
| 115 | * milliseconds for an answer to arrive. The answer will bypass |
| 116 | * the ordinary queuing mechanism and will be delivered before any |
| 117 | * other asynchronous message. The answer need to have the |
| 118 | * getLastUOID set to the UOID of the message send with |
| 119 | * sendAndWait. If the answer does not arrive withing the specified |
| 120 | * time interval, the method returns <code>null</code> and the |
| 121 | * answer will be handled as if it was an ordinary asynchronous |
| 122 | * message. |
| 123 | * |
| 124 | * @param envelope the cell message to be sent. |
| 125 | * @param timeout milliseconds to wait for an answer. |
| 126 | * @return the answer or null if the timeout was reached. |
| 127 | * @throws SerializationException if the payload object of this |
| 128 | * message is not serializable. |
| 129 | * @throws NoRouteToCellException if the destination |
| 130 | * couldnot be reached. |
| 131 | */ |
| 132 | protected CellMessage sendAndWait(CellMessage envelope, long timeout) |
| 133 | throws SerializationException, |
| 134 | NoRouteToCellException, |
| 135 | InterruptedException |
| 136 | { |
| 137 | return _endpoint.sendAndWait(envelope, timeout); |
| 138 | } |
| 139 | |
| 140 | /** |
| 141 | * Provides information about the host cell. |
| 142 | * |
| 143 | * Depending on the cell, a subclass of CellInfo with additional |
| 144 | * information may be returned instead. |
| 145 | * |
| 146 | * @return The cell information encapsulated in a CellInfo object. |
| 147 | */ |
| 148 | protected CellInfo getCellInfo() |
| 149 | { |
| 150 | return _endpoint.getCellInfo(); |
| 151 | } |
| 152 | |
| 153 | /** |
| 154 | * Returns the name of the cell hosting this component. |
| 155 | */ |
| 156 | protected String getCellName() |
| 157 | { |
| 158 | return getCellInfo().getCellName(); |
| 159 | } |
| 160 | |
| 161 | /** |
| 162 | * Returns the name of the domain hosting the cell hosting this |
| 163 | * component. |
| 164 | */ |
| 165 | protected String getCellDomainName() |
| 166 | { |
| 167 | return getCellInfo().getDomainName(); |
| 168 | } |
| 169 | |
| 170 | /** |
| 171 | * Returns the domain context. The domain context is shared by all |
| 172 | * cells in a domain. |
| 173 | */ |
| 174 | protected Map<String,Object> getDomainContext() |
| 175 | { |
| 176 | return _endpoint.getDomainContext(); |
| 177 | } |
| 178 | |
| 179 | /** |
| 180 | * Returns the cell command line arguments provided when the cell |
| 181 | * was created. |
| 182 | */ |
| 183 | protected Args getArgs() |
| 184 | { |
| 185 | return _endpoint.getArgs(); |
| 186 | } |
| 187 | } |