Use lambdas where possible in QueryRunner, fix java6 compilation

This commit is contained in:
Travis Burtrum 2017-07-03 00:00:03 -04:00
parent 133c4eb8c9
commit 5d9ff80863
4 changed files with 83 additions and 20 deletions

View File

@ -14,7 +14,7 @@ import static com.moparisthebest.jdbc.TryClose.tryClose;
public class QueryRunner<T extends JdbcMapper> {
private static final int defaultRetryCount = 10;
private static final DelayStrategy defaultDelayStrategy = exponentialBackoff(1000, 30000, 2000);
private static final DelayStrategy defaultDelayStrategy = exponentialBackoff(1000, 30000, 2000, 10);
private static final ExecutorService defaultExecutorService = Executors.newCachedThreadPool(); // todo: good or bad default?
private final Factory<T> factory;
@ -117,23 +117,30 @@ public class QueryRunner<T extends JdbcMapper> {
} catch (SQLException e) {
lastException = e;
try {
Thread.sleep(delayStrategy.getDelay(x));
Thread.sleep(delayStrategy.getDelay(++x));
} catch (InterruptedException e2) {
Thread.interrupted();
}
}
} while (++x <= retryCount);
} while (x <= retryCount);
throw lastException;
}
public <E> Future<E> runRetryFuture(final Runner<T, E> query) {
// todo: sleeps in thread, could use ScheduledExecutorService maybe?
return executorService.submit(new Callable<E>() {
@Override
public E call() throws Exception {
return runRetry(query);
}
});
return executorService.submit(
//IFJAVA8_START
() -> runRetry(query)
//IFJAVA8_END
/*IFJAVA6_START
new Callable<E>() {
@Override
public E call() throws Exception {
return runRetry(query);
}
}
IFJAVA6_END*/
);
}
//IFJAVA8_START
@ -170,31 +177,74 @@ public class QueryRunner<T extends JdbcMapper> {
*
* @author Robert Buck (buck.robert.j@gmail.com)
*/
public static DelayStrategy exponentialBackoff(final long minBackoff, final long maxBackoff, final long slotTime) {
return new DelayStrategy() {
public static DelayStrategy exponentialBackoff(final long minBackoff, final long maxBackoff, final long slotTime, final long maxContentionPeriods) {
return
/*IFJAVA6_START
new DelayStrategy() {
@Override
public long getDelay(final int attempt) {
final int MAX_CONTENTION_PERIODS = 10;
return attempt == 0 ? 0 : Math.min(minBackoff + ThreadLocalRandom.current().nextInt(2 << Math.min(attempt, MAX_CONTENTION_PERIODS - 1)) * slotTime, maxBackoff);
return
IFJAVA6_END*/
//IFJAVA8_START
(attempt) ->
//IFJAVA8_END
attempt == 0 ? 0 : Math.min(minBackoff + ThreadLocalRandom.current().nextInt(2 << Math.min(attempt, maxContentionPeriods - 1)) * slotTime, maxBackoff);
/*IFJAVA6_START
}
};
IFJAVA6_END*/
}
public static DelayStrategy fixedDelay(final long delay) {
return new DelayStrategy() {
return
/*IFJAVA6_START
new DelayStrategy() {
@Override
public long getDelay(final int attempt) {
return delay;
return
IFJAVA6_END*/
//IFJAVA8_START
(attempt) ->
//IFJAVA8_END
delay;
/*IFJAVA6_START
}
};
IFJAVA6_END*/
}
public static DelayStrategy incrementalDelay(final long initialInterval, final long incrementalInterval) {
return new DelayStrategy() {
return
/*IFJAVA6_START
new DelayStrategy() {
@Override
public long getDelay(final int attempt) {
return initialInterval + incrementalInterval * attempt;
return
IFJAVA6_END*/
//IFJAVA8_START
(attempt) ->
//IFJAVA8_END
initialInterval + incrementalInterval * attempt;
/*IFJAVA6_START
}
};
IFJAVA6_END*/
}
/*IFJAVA6_START
// terrible, I know, use java8
private static class ThreadLocalRandom {
private static final ThreadLocal<java.util.Random> randomThreadLocal = new ThreadLocal<java.util.Random>() {
@Override
protected java.util.Random initialValue() {
return new java.util.Random();
}
};
private static java.util.Random current() {
return randomThreadLocal.get();
}
}
IFJAVA6_END*/
}

11
pom.xml
View File

@ -218,6 +218,9 @@
<excludes>
<exclude>target/**</exclude>
</excludes>
<regexFlags>
<regexFlag>LITERAL</regexFlag>
</regexFlags>
<replacements>
<replacement>
<token>//IFJAVA8_START</token>
@ -227,6 +230,14 @@
<token>//IFJAVA8_END</token>
<value>IFJAVA8_END*/</value>
</replacement>
<replacement>
<token>/*IFJAVA6_START</token>
<value>//IFJAVA6_START</value>
</replacement>
<replacement>
<token>IFJAVA6_END*/</token>
<value>//IFJAVA6_END</value>
</replacement>
</replacements>
</configuration>
</plugin>

View File

@ -25,8 +25,8 @@ public class QueryRunnerTest {
final Person actual =
//qr.run(
//qr.runRetry(
//qr.runRetryFuture(
qr.runRetryCompletableFuture(
qr.runRetryFuture(
//qr.runRetryCompletableFuture(
new QueryRunner.Runner<QueryMapper, Person>() {
@Override
public Person run(final QueryMapper qm) throws SQLException {

View File

@ -1,2 +1,4 @@
#!/bin/sh
find */src/{main,test}/java -type f -name '*.java' -print0 | xargs -0 sed -i -e 's@/\*IFJAVA8_START@//IFJAVA8_START@' -e 's@IFJAVA8_END\*/@//IFJAVA8_END@'
find */src/{main,test}/java -type f -name '*.java' -print0 | xargs -0 sed -i \
-e 's@/\*IFJAVA8_START@//IFJAVA8_START@' -e 's@IFJAVA8_END\*/@//IFJAVA8_END@' \
-e 's@//IFJAVA6_START@/*IFJAVA6_START@' -e 's@//IFJAVA6_END@IFJAVA6_END*/@'