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Java 11 support for #984 #987 (l) (#1190)

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* Java 11 support: lazy-loading pattern

* Java 11 support: layers pattern

* Java 11 support: leader-election/lazy-loading patterns
This commit is contained in:
Zhang WH
2020-03-23 02:02:45 +08:00
committed by GitHub
parent 0ad67c8726
commit 67edeb806d
23 changed files with 238 additions and 243 deletions
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12
lazy-loading/src/main/java/com/iluwatar/lazy/loading/App.java
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@ -46,18 +46,18 @@ public class App {
public static void main(String[] args) {
// Simple lazy loader - not thread safe
HolderNaive holderNaive = new HolderNaive();
Heavy heavy = holderNaive.getHeavy();
var holderNaive = new HolderNaive();
var heavy = holderNaive.getHeavy();
LOGGER.info("heavy={}", heavy);
// Thread safe lazy loader, but with heavy synchronization on each access
HolderThreadSafe holderThreadSafe = new HolderThreadSafe();
Heavy another = holderThreadSafe.getHeavy();
var holderThreadSafe = new HolderThreadSafe();
var another = holderThreadSafe.getHeavy();
LOGGER.info("another={}", another);
// The most efficient lazy loader utilizing Java 8 features
Java8Holder java8Holder = new Java8Holder();
Heavy next = java8Holder.getHeavy();
var java8Holder = new Java8Holder();
var next = java8Holder.getHeavy();
LOGGER.info("next={}", next);
}
}

2
lazy-loading/src/test/java/com/iluwatar/lazy/loading/HolderNaiveTest.java
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@ -36,7 +36,7 @@ public class HolderNaiveTest extends AbstractHolderTest {
@Override
Heavy getInternalHeavyValue() throws Exception {
final Field holderField = HolderNaive.class.getDeclaredField("heavy");
final var holderField = HolderNaive.class.getDeclaredField("heavy");
holderField.setAccessible(true);
return (Heavy) holderField.get(this.holder);
}

2
lazy-loading/src/test/java/com/iluwatar/lazy/loading/HolderThreadSafeTest.java
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@ -36,7 +36,7 @@ public class HolderThreadSafeTest extends AbstractHolderTest {
@Override
Heavy getInternalHeavyValue() throws Exception {
final Field holderField = HolderThreadSafe.class.getDeclaredField("heavy");
final var holderField = HolderThreadSafe.class.getDeclaredField("heavy");
holderField.setAccessible(true);
return (Heavy) holderField.get(this.holder);
}

8
lazy-loading/src/test/java/com/iluwatar/lazy/loading/Java8HolderTest.java
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@ -38,16 +38,16 @@ public class Java8HolderTest extends AbstractHolderTest {
@Override
Heavy getInternalHeavyValue() throws Exception {
final Field holderField = Java8Holder.class.getDeclaredField("heavy");
final var holderField = Java8Holder.class.getDeclaredField("heavy");
holderField.setAccessible(true);
final Supplier<Heavy> supplier = (Supplier<Heavy>) holderField.get(this.holder);
final Class<? extends Supplier> supplierClass = supplier.getClass();
final var supplier = (Supplier<Heavy>) holderField.get(this.holder);
final var supplierClass = supplier.getClass();
// This is a little fishy, but I don't know another way to test this:
// The lazy holder is at first a lambda, but gets replaced with a new supplier after loading ...
if (supplierClass.isLocalClass()) {
final Field instanceField = supplierClass.getDeclaredField("heavyInstance");
final var instanceField = supplierClass.getDeclaredField("heavyInstance");
instanceField.setAccessible(true);
return (Heavy) instanceField.get(supplier);
} else {