98 lines
1.8 KiB
Java
98 lines
1.8 KiB
Java
package it.cavallium.dbengine.database;
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import it.cavallium.buffer.Buf;
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import java.util.NoSuchElementException;
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import java.util.Objects;
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import java.util.Optional;
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import java.util.function.Consumer;
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import java.util.function.Function;
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import org.jetbrains.annotations.NotNull;
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import org.jetbrains.annotations.Nullable;
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public final class OptionalBuf {
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private static final OptionalBuf EMPTY = new OptionalBuf(null);
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private final Buf buffer;
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private OptionalBuf(@Nullable Buf buffer) {
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this.buffer = buffer;
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}
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public static OptionalBuf ofNullable(@Nullable Buf buffer) {
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return new OptionalBuf(buffer);
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}
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public static OptionalBuf of(@NotNull Buf buffer) {
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Objects.requireNonNull(buffer);
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return new OptionalBuf(buffer);
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}
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public static OptionalBuf empty() {
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return EMPTY;
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}
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@Override
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public String toString() {
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if (buffer != null) {
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return buffer.toString();
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} else {
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return "(empty)";
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}
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}
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@Override
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public boolean equals(Object o) {
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if (this == o) {
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return true;
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}
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if (o == null || getClass() != o.getClass()) {
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return false;
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}
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OptionalBuf that = (OptionalBuf) o;
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return Objects.equals(buffer, that.buffer);
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}
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@Override
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public int hashCode() {
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return buffer != null ? buffer.hashCode() : 0;
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}
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public Buf get() {
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if (buffer == null) {
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throw new NoSuchElementException();
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}
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return buffer;
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}
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public Buf orElse(Buf alternative) {
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if (buffer == null) {
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return alternative;
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}
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return buffer;
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}
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public void ifPresent(Consumer<Buf> consumer) {
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if (buffer != null) {
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consumer.accept(buffer);
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}
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}
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public boolean isPresent() {
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return buffer != null;
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}
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public boolean isEmpty() {
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return buffer == null;
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}
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public <U> Optional<U> map(Function<Buf, U> mapper) {
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if (buffer != null) {
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return Optional.of(mapper.apply(buffer));
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} else {
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return Optional.empty();
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}
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}
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}
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