currenttransaction.html

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<a name="152" href="#152">152</a> <em>     * Returns the transaction associated with the current thread for this</em>
<a name="153" href="#153">153</a> <em>     * environment, or null if no transaction is active.</em>
<a name="154" href="#154">154</a> <em>     */</em>
<a name="155" href="#155">155</a>     <strong>public</strong> <strong>final</strong> Transaction getTransaction() {
<a name="156" href="#156">156</a> 
<a name="157" href="#157">157</a>         Trans trans = (Trans) localTrans.get();
<a name="158" href="#158">158</a>         <strong>return</strong> (trans != <strong>null</strong>) ? trans.txn : <strong>null</strong>;
<a name="159" href="#159">159</a>     }
<a name="160" href="#160">160</a> 
<a name="161" href="#161">161</a>     <em>/**<em>*</em></em>
<a name="162" href="#162">162</a> <em>     * Returns whether auto-commit may be performed by the collections API.</em>
<a name="163" href="#163">163</a> <em>     * True is returned if no collections API transaction is currently active,</em>
<a name="164" href="#164">164</a> <em>     * and no XA transaction is currently active.</em>
<a name="165" href="#165">165</a> <em>     */</em>
<a name="166" href="#166">166</a>     <strong>boolean</strong> isAutoCommitAllowed()
<a name="167" href="#167">167</a> 	throws DatabaseException {
<a name="168" href="#168">168</a> 
<a name="169" href="#169">169</a>         <strong>return</strong> getTransaction() == <strong>null</strong> &amp;&amp;
<a name="170" href="#170">170</a>                DbCompat.getThreadTransaction(env) == <strong>null</strong>;
<a name="171" href="#171">171</a>     }
<a name="172" href="#172">172</a> 
<a name="173" href="#173">173</a>     <em>/**<em>*</em></em>
<a name="174" href="#174">174</a> <em>     * Begins a new transaction for this environment and associates it with</em>
<a name="175" href="#175">175</a> <em>     * the current thread.  If a transaction is already active for this</em>
<a name="176" href="#176">176</a> <em>     * environment and thread, a nested transaction will be created.</em>
<a name="177" href="#177">177</a> <em>     *</em>
<a name="178" href="#178">178</a> <em>     * @param config the transaction configuration used for calling</em>
<a name="179" href="#179">179</a> <em>     * {@link Environment#beginTransaction}, or null to use the default</em>
<a name="180" href="#180">180</a> <em>     * configuration.</em>
<a name="181" href="#181">181</a> <em>     *</em>
<a name="182" href="#182">182</a> <em>     * @return the new transaction.</em>
<a name="183" href="#183">183</a> <em>     *</em>
<a name="184" href="#184">184</a> <em>     * @throws DatabaseException if the transaction cannot be started, in which</em>
<a name="185" href="#185">185</a> <em>     * case any existing transaction is not affected.</em>
<a name="186" href="#186">186</a> <em>     *</em>
<a name="187" href="#187">187</a> <em>     * @throws IllegalStateException if a transaction is already active and</em>
<a name="188" href="#188">188</a> <em>     * nested transactions are not supported by the environment.</em>
<a name="189" href="#189">189</a> <em>     */</em>
<a name="190" href="#190">190</a>     <strong>public</strong> <strong>final</strong> Transaction beginTransaction(TransactionConfig config)
<a name="191" href="#191">191</a>         throws DatabaseException {
<a name="192" href="#192">192</a> 
<a name="193" href="#193">193</a>         Trans trans = (Trans) localTrans.get();
<a name="194" href="#194">194</a>         <strong>if</strong> (trans != <strong>null</strong>) {
<a name="195" href="#195">195</a>             <strong>if</strong> (trans.txn != <strong>null</strong>) {
<a name="196" href="#196">196</a>                 <strong>if</strong> (!DbCompat.NESTED_TRANSACTIONS) {
<a name="197" href="#197">197</a>                     <strong>throw</strong> <strong>new</strong> IllegalStateException(
<a name="198" href="#198">198</a>                             <span class="string">"Nested transactions are not supported"</span>);
<a name="199" href="#199">199</a>                 }
<a name="200" href="#200">200</a>                 Transaction parentTxn = trans.txn;
<a name="201" href="#201">201</a>                 trans = <strong>new</strong> Trans(trans, config);
<a name="202" href="#202">202</a>                 trans.txn = env.beginTransaction(parentTxn, config);
<a name="203" href="#203">203</a>                 localTrans.set(trans);
<a name="204" href="#204">204</a>             } <strong>else</strong> {
<a name="205" href="#205">205</a>                 trans.txn = env.beginTransaction(<strong>null</strong>, config);
<a name="206" href="#206">206</a>                 trans.config = config;
<a name="207" href="#207">207</a>             }
<a name="208" href="#208">208</a>         } <strong>else</strong> {
<a name="209" href="#209">209</a>             trans = <strong>new</strong> Trans(<strong>null</strong>, config);
<a name="210" href="#210">210</a>             trans.txn = env.beginTransaction(<strong>null</strong>, config);
<a name="211" href="#211">211</a>             localTrans.set(trans);
<a name="212" href="#212">212</a>         }
<a name="213" href="#213">213</a>         <strong>return</strong> trans.txn;
<a name="214" href="#214">214</a>     }
<a name="215" href="#215">215</a> 
<a name="216" href="#216">216</a>     <em>/**<em>*</em></em>
<a name="217" href="#217">217</a> <em>     * Commits the transaction that is active for the current thread for this</em>
<a name="218" href="#218">218</a> <em>     * environment and makes the parent transaction (if any) the current</em>
<a name="219" href="#219">219</a> <em>     * transaction.</em>
<a name="220" href="#220">220</a> <em>     *</em>
<a name="221" href="#221">221</a> <em>     * @return the parent transaction or null if the committed transaction was</em>
<a name="222" href="#222">222</a> <em>     * not nested.</em>
<a name="223" href="#223">223</a> <em>     *</em>
<a name="224" href="#224">224</a> <em>     * @throws DatabaseException if an error occurs committing the transaction.</em>
<a name="225" href="#225">225</a> <em>     * The transaction will still be closed and the parent transaction will</em>
<a name="226" href="#226">226</a> <em>     * become the current transaction.</em>
<a name="227" href="#227">227</a> <em>     *</em>
<a name="228" href="#228">228</a> <em>     * @throws IllegalStateException if no transaction is active for the</em>
<a name="229" href="#229">229</a> <em>     * current thread for this environment.</em>
<a name="230" href="#230">230</a> <em>     */</em>
<a name="231" href="#231">231</a>     <strong>public</strong> <strong>final</strong> Transaction commitTransaction()
<a name="232" href="#232">232</a>         throws DatabaseException, IllegalStateException {
<a name="233" href="#233">233</a> 
<a name="234" href="#234">234</a>         Trans trans = (Trans) localTrans.get();
<a name="235" href="#235">235</a>         <strong>if</strong> (trans != <strong>null</strong> &amp;&amp; trans.txn != <strong>null</strong>) {
<a name="236" href="#236">236</a>             Transaction parent = closeTxn(trans);
<a name="237" href="#237">237</a>             trans.txn.commit();
<a name="238" href="#238">238</a>             <strong>return</strong> parent;
<a name="239" href="#239">239</a>         } <strong>else</strong> {
<a name="240" href="#240">240</a>             <strong>throw</strong> <strong>new</strong> IllegalStateException(<span class="string">"No transaction is active"</span>);
<a name="241" href="#241">241</a>         }
<a name="242" href="#242">242</a>     }
<a name="243" href="#243">243</a> 
<a name="244" href="#244">244</a>     <em>/**<em>*</em></em>
<a name="245" href="#245">245</a> <em>     * Aborts the transaction that is active for the current thread for this</em>
<a name="246" href="#246">246</a> <em>     * environment and makes the parent transaction (if any) the current</em>
<a name="247" href="#247">247</a> <em>     * transaction.</em>
<a name="248" href="#248">248</a> <em>     *</em>
<a name="249" href="#249">249</a> <em>     * @return the parent transaction or null if the aborted transaction was</em>
<a name="250" href="#250">250</a> <em>     * not nested.</em>
<a name="251" href="#251">251</a> <em>     *</em>
<a name="252" href="#252">252</a> <em>     * @throws DatabaseException if an error occurs aborting the transaction.</em>
<a name="253" href="#253">253</a> <em>     * The transaction will still be closed and the parent transaction will</em>
<a name="254" href="#254">254</a> <em>     * become the current transaction.</em>
<a name="255" href="#255">255</a> <em>     *</em>
<a name="256" href="#256">256</a> <em>     * @throws IllegalStateException if no transaction is active for the</em>
<a name="257" href="#257">257</a> <em>     * current thread for this environment.</em>
<a name="258" href="#258">258</a> <em>     */</em>
<a name="259" href="#259">259</a>     <strong>public</strong> <strong>final</strong> Transaction abortTransaction()
<a name="260" href="#260">260</a>         throws DatabaseException, IllegalStateException {
<a name="261" href="#261">261</a> 
<a name="262" href="#262">262</a>         Trans trans = (Trans) localTrans.get();
<a name="263" href="#263">263</a>         <strong>if</strong> (trans != <strong>null</strong> &amp;&amp; trans.txn != <strong>null</strong>) {
<a name="264" href="#264">264</a>             Transaction parent = closeTxn(trans);
<a name="265" href="#265">265</a>             trans.txn.abort();
<a name="266" href="#266">266</a>             <strong>return</strong> parent;
<a name="267" href="#267">267</a>         } <strong>else</strong> {
<a name="268" href="#268">268</a>             <strong>throw</strong> <strong>new</strong> IllegalStateException(<span class="string">"No transaction is active"</span>);
<a name="269" href="#269">269</a>         }
<a name="270" href="#270">270</a>     }
<a name="271" href="#271">271</a> 
<a name="272" href="#272">272</a>     <em>/**<em>*</em></em>
<a name="273" href="#273">273</a> <em>     * Returns whether the current transaction is a readUncommitted</em>
<a name="274" href="#274">274</a> <em>     * transaction.</em>
<a name="275" href="#275">275</a> <em>     */</em>
<a name="276" href="#276">276</a>     <strong>final</strong> <strong>boolean</strong> isReadUncommitted() {
<a name="277" href="#277">277</a> 
<a name="278" href="#278">278</a>         Trans trans = (Trans) localTrans.get();
<a name="279" href="#279">279</a>         <strong>if</strong> (trans != <strong>null</strong> &amp;&amp; trans.config != <strong>null</strong>) {
<a name="280" href="#280">280</a>             <strong>return</strong> trans.config.getReadUncommitted();
<a name="281" href="#281">281</a>         } <strong>else</strong> {
<a name="282" href="#282">282</a>             <strong>return</strong> false;
<a name="283" href="#283">283</a>         }
<a name="284" href="#284">284</a>     }
<a name="285" href="#285">285</a> 
<a name="286" href="#286">286</a>     <strong>private</strong> Transaction closeTxn(Trans trans) {
<a name="287" href="#287">287</a> 
<a name="288" href="#288">288</a>         localTrans.set(trans.parent);
<a name="289" href="#289">289</a>         <strong>return</strong> (trans.parent != <strong>null</strong>) ? trans.parent.txn : <strong>null</strong>;
<a name="290" href="#290">290</a>     }
<a name="291" href="#291">291</a> 
<a name="292" href="#292">292</a>     <strong>private</strong> <strong>static</strong> <strong>class</strong> Trans {
<a name="293" href="#293">293</a> 
<a name="294" href="#294">294</a>         <strong>private</strong> Trans parent;
<a name="295" href="#295">295</a>         <strong>private</strong> Transaction txn;
<a name="296" href="#296">296</a>         <strong>private</strong> TransactionConfig config;
<a name="297" href="#297">297</a> 
<a name="298" href="#298">298</a>         <strong>private</strong> Trans(Trans parent, TransactionConfig config) {
<a name="299" href="#299">299</a> 
<a name="300" href="#300">300</a>             <strong>this</strong>.parent = parent;
<a name="301" href="#301">301</a>             <strong>this</strong>.config = config;
<a name="302" href="#302">302</a>         }
<a name="303" href="#303">303</a>     }
<a name="304" href="#304">304</a> 
<a name="305" href="#305">305</a>     <em>/**<em>*</em></em>
<a name="306" href="#306">306</a> <em>     * Opens a cursor for a given database, dup'ing an existing CDB cursor if</em>
<a name="307" href="#307">307</a> <em>     * one is open for the current thread.</em>
<a name="308" href="#308">308</a> <em>     */</em>
<a name="309" href="#309">309</a>     Cursor openCursor(Database db, CursorConfig cursorConfig,
<a name="310" href="#310">310</a>                       <strong>boolean</strong> writeCursor, Transaction txn)
<a name="311" href="#311">311</a>         throws DatabaseException {