org.cloudfoundry.multiapps.controller.process.variables.ImmutableSimpleVariable Maven / Gradle / Ivy
package org.cloudfoundry.multiapps.controller.process.variables;
import java.util.ArrayList;
import java.util.List;
import java.util.Objects;
import org.cloudfoundry.multiapps.common.Nullable;
/**
* Immutable implementation of {@link SimpleVariable}.
*
* Use the builder to create immutable instances:
* {@code ImmutableSimpleVariable.builder()}.
*/
@SuppressWarnings({"all"})
public final class ImmutableSimpleVariable
extends SimpleVariable {
private final String name;
private final @Nullable T defaultValue;
private ImmutableSimpleVariable(String name, @Nullable T defaultValue) {
this.name = name;
this.defaultValue = defaultValue;
}
/**
* @return The value of the {@code name} attribute
*/
@Override
public String getName() {
return name;
}
/**
* @return The value of the {@code defaultValue} attribute
*/
@Override
public @Nullable T getDefaultValue() {
return defaultValue;
}
/**
* Copy the current immutable object by setting a value for the {@link SimpleVariable#getName() name} attribute.
* An equals check used to prevent copying of the same value by returning {@code this}.
* @param value A new value for name
* @return A modified copy of the {@code this} object
*/
public final ImmutableSimpleVariable withName(String value) {
String newValue = Objects.requireNonNull(value, "name");
if (this.name.equals(newValue)) return this;
return new ImmutableSimpleVariable<>(newValue, this.defaultValue);
}
/**
* Copy the current immutable object by setting a value for the {@link SimpleVariable#getDefaultValue() defaultValue} attribute.
* A shallow reference equality check is used to prevent copying of the same value by returning {@code this}.
* @param value A new value for defaultValue (can be {@code null})
* @return A modified copy of the {@code this} object
*/
public final ImmutableSimpleVariable withDefaultValue(@Nullable T value) {
if (this.defaultValue == value) return this;
return new ImmutableSimpleVariable<>(this.name, value);
}
/**
* This instance is equal to all instances of {@code ImmutableSimpleVariable} that have equal attribute values.
* @return {@code true} if {@code this} is equal to {@code another} instance
*/
@Override
public boolean equals(Object another) {
if (this == another) return true;
return another instanceof ImmutableSimpleVariable
&& equalTo(0, (ImmutableSimpleVariable) another);
}
private boolean equalTo(int synthetic, ImmutableSimpleVariable another) {
return name.equals(another.name)
&& Objects.equals(defaultValue, another.defaultValue);
}
/**
* Computes a hash code from attributes: {@code name}, {@code defaultValue}.
* @return hashCode value
*/
@Override
public int hashCode() {
int h = 5381;
h += (h << 5) + name.hashCode();
h += (h << 5) + Objects.hashCode(defaultValue);
return h;
}
/**
* Prints the immutable value {@code SimpleVariable} with attribute values.
* @return A string representation of the value
*/
@Override
public String toString() {
return "SimpleVariable{"
+ "name=" + name
+ ", defaultValue=" + defaultValue
+ "}";
}
/**
* Creates an immutable copy of a {@link SimpleVariable} value.
* Uses accessors to get values to initialize the new immutable instance.
* If an instance is already immutable, it is returned as is.
* @param generic parameter T
* @param instance The instance to copy
* @return A copied immutable SimpleVariable instance
*/
public static ImmutableSimpleVariable copyOf(SimpleVariable instance) {
if (instance instanceof ImmutableSimpleVariable) {
return (ImmutableSimpleVariable) instance;
}
return ImmutableSimpleVariable.builder()
.from(instance)
.build();
}
/**
* Creates a builder for {@link ImmutableSimpleVariable ImmutableSimpleVariable}.
*
* ImmutableSimpleVariable.<T>builder()
* .name(String) // required {@link SimpleVariable#getName() name}
* .defaultValue(T | null) // nullable {@link SimpleVariable#getDefaultValue() defaultValue}
* .build();
*
* @param generic parameter T
* @return A new ImmutableSimpleVariable builder
*/
public static ImmutableSimpleVariable.Builder builder() {
return new ImmutableSimpleVariable.Builder<>();
}
/**
* Builds instances of type {@link ImmutableSimpleVariable ImmutableSimpleVariable}.
* Initialize attributes and then invoke the {@link #build()} method to create an
* immutable instance.
* {@code Builder} is not thread-safe and generally should not be stored in a field or collection,
* but instead used immediately to create instances.
*/
public static final class Builder {
private static final long INIT_BIT_NAME = 0x1L;
private long initBits = 0x1L;
private String name;
private T defaultValue;
private Builder() {
}
/**
* Fill a builder with attribute values from the provided {@code org.cloudfoundry.multiapps.controller.process.variables.Variable} instance.
* @param instance The instance from which to copy values
* @return {@code this} builder for use in a chained invocation
*/
public final Builder from(Variable instance) {
Objects.requireNonNull(instance, "instance");
from((short) 0, (Object) instance);
return this;
}
/**
* Fill a builder with attribute values from the provided {@code org.cloudfoundry.multiapps.controller.process.variables.SimpleVariable} instance.
* @param instance The instance from which to copy values
* @return {@code this} builder for use in a chained invocation
*/
public final Builder from(SimpleVariable instance) {
Objects.requireNonNull(instance, "instance");
from((short) 0, (Object) instance);
return this;
}
@SuppressWarnings("unchecked")
private void from(short _unused, Object object) {
if (object instanceof Variable) {
Variable instance = (Variable) object;
this.name(instance.getName());
@Nullable T defaultValueValue = instance.getDefaultValue();
if (defaultValueValue != null) {
defaultValue(defaultValueValue);
}
}
}
/**
* Initializes the value for the {@link SimpleVariable#getName() name} attribute.
* @param name The value for name
* @return {@code this} builder for use in a chained invocation
*/
public final Builder name(String name) {
this.name = Objects.requireNonNull(name, "name");
initBits &= ~INIT_BIT_NAME;
return this;
}
/**
* Initializes the value for the {@link SimpleVariable#getDefaultValue() defaultValue} attribute.
* @param defaultValue The value for defaultValue (can be {@code null})
* @return {@code this} builder for use in a chained invocation
*/
public final Builder defaultValue(@Nullable T defaultValue) {
this.defaultValue = defaultValue;
return this;
}
/**
* Builds a new {@link ImmutableSimpleVariable ImmutableSimpleVariable}.
* @return An immutable instance of SimpleVariable
* @throws java.lang.IllegalStateException if any required attributes are missing
*/
public ImmutableSimpleVariable build() {
if (initBits != 0) {
throw new IllegalStateException(formatRequiredAttributesMessage());
}
return new ImmutableSimpleVariable<>(name, defaultValue);
}
private String formatRequiredAttributesMessage() {
List attributes = new ArrayList<>();
if ((initBits & INIT_BIT_NAME) != 0) attributes.add("name");
return "Cannot build SimpleVariable, some of required attributes are not set " + attributes;
}
}
}