Here are the examples of the java api class java.util.Optional taken from open source projects.
1. NamedSingletonsFactory#get()
Project: restheart
File: NamedSingletonsFactory.java
File: NamedSingletonsFactory.java
public Object get(String group, String name) throws IllegalArgumentException { Optional op = CACHE.get(group + SEPARATOR + name); if (op == null) { throw new IllegalArgumentException("no singleton configured with name : " + name); } if (op.isPresent()) { return op.get(); } else { throw new IllegalArgumentException("no singleton configured with name : " + name); } }
2. OptionalExampleTest#examples()
Project: java-8-lambdas-exercises
File: OptionalExampleTest.java
File: OptionalExampleTest.java
@Test public void examples() { // BEGIN value_creation Optional<String> a = Optional.of("a"); assertEquals("a", a.get()); // END value_creation // BEGIN is_present Optional emptyOptional = Optional.empty(); Optional alsoEmpty = Optional.ofNullable(null); assertFalse(emptyOptional.isPresent()); // a is defined above assertTrue(a.isPresent()); // END is_present // BEGIN orElse assertEquals("b", emptyOptional.orElse("b")); assertEquals("c", emptyOptional.orElseGet(() -> "c")); // END orElse }
3. InvokeDynamicComprehender#empty()
Project: cyclops-react
File: InvokeDynamicComprehender.java
File: InvokeDynamicComprehender.java
@Override public Object empty() { InvokeDynamic dyn = new InvokeDynamic(); Optional o = dyn.execute(Arrays.asList("empty", "of", "cons", "none", "nil", "left", "failure", "secondary"), type.get()); return o.get(); }
4. InvokeDynamicComprehender#of()
Project: cyclops-react
File: InvokeDynamicComprehender.java
File: InvokeDynamicComprehender.java
@Override public Object of(Object o) { InvokeDynamic dyn = new InvokeDynamic(); Optional ob = dyn.execute(Arrays.asList("of", "singleton", "some", "right", "success", "primary"), type.get(), o); return ob.get(); }
5. RightProjectionComprehender#resolveForCrossTypeFlatMap()
Project: cyclops
File: RightProjectionComprehender.java
File: RightProjectionComprehender.java
public Object resolveForCrossTypeFlatMap(Comprehender comp, RightProjection apply) { Optional present = apply.toJavaOptional(); if (present.isPresent()) return comp.of(apply.get()); else return comp.empty(); }
6. LeftProjectionComprehender#resolveForCrossTypeFlatMap()
Project: cyclops
File: LeftProjectionComprehender.java
File: LeftProjectionComprehender.java
public Object resolveForCrossTypeFlatMap(Comprehender comp, LeftProjection apply) { Optional present = apply.toJavaOptional(); if (present.isPresent()) return comp.of(apply.get()); else return comp.empty(); }