org.eclipse.microprofile.metrics.MetadataBuilder Maven / Gradle / Ivy
/*
**********************************************************************
* Copyright (c) 2018, 2022 Contributors to the Eclipse Foundation
* 2018 Red Hat, Inc. and/or its affiliates
* and other contributors as indicated by the @author tags.
*
* See the NOTICES file(s) distributed with this work for additional
* information regarding copyright ownership.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* You may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*
* SPDX-License-Identifier: Apache-2.0
**********************************************************************/
package org.eclipse.microprofile.metrics;
import java.util.Objects;
/**
* The {@link Metadata} builder.
*
* All values are considered "not present" by default. Name must be set before {@link #build()} is called.
*/
public class MetadataBuilder {
private String name;
private String description;
private String unit;
MetadataBuilder(Metadata metadata) {
this.name = metadata.getName();
metadata.description().ifPresent(this::withDescription);
metadata.unit().ifPresent(this::withUnit);
}
public MetadataBuilder() {
}
/**
* Sets the name. Does not accept null.
*
* @param name
* the name
* @return the builder instance
* @throws NullPointerException
* when name is null
* @throws IllegalArgumentException
* when name is empty
*/
public MetadataBuilder withName(String name) {
this.name = Objects.requireNonNull(name, "name is required");
if ("".equals(name)) {
throw new IllegalArgumentException("Name must not be empty");
}
return this;
}
/**
* Sets the description.
*
* @param description
* the name, empty string is considered as "not present" (null)
* @return the builder instance
*/
public MetadataBuilder withDescription(String description) {
this.description = "".equals(description) ? null : description;
return this;
}
/**
* Sets the unit.
*
* @param unit
* the unit, {@link MetricUnits#NONE} is considered as "not present" (null)
* @return the builder instance
*/
public MetadataBuilder withUnit(String unit) {
this.unit = MetricUnits.NONE.equals(unit) ? null : unit;
return this;
}
/**
* @return An object implementing {@link Metadata} from the provided properties
* @throws IllegalStateException
* when either name is null
*/
public Metadata build() {
if (Objects.isNull(name)) {
throw new IllegalStateException("Name is required");
}
return new DefaultMetadata(name, description, unit);
}
}