/*
* Copyright 2014 Netflix, Inc.
*
* 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.
*/
package com.netflix.servo.tag;
import com.netflix.servo.util.Iterables;
import com.netflix.servo.util.Preconditions;
import com.netflix.servo.util.Strings;
import java.util.Arrays;
import java.util.Collections;
import java.util.Iterator;
import java.util.Map;
import java.util.SortedMap;
import java.util.TreeMap;
/**
* Immutable tag list.
*/
public final class BasicTagList implements TagList {
/**
* An empty tag list.
*/
public static final TagList EMPTY = new BasicTagList(Collections.<Tag>emptySet());
private final SmallTagMap tagMap;
private SortedMap<String, String> sortedTaglist;
/**
* Create a BasicTagList from a {@link SmallTagMap}.
*/
public BasicTagList(SmallTagMap tagMap) {
this.tagMap = tagMap;
}
/**
* Creates a new instance with a fixed set of tags.
*
* @param entries entries to include in this tag list
*/
public BasicTagList(Iterable<Tag> entries) {
SmallTagMap.Builder builder = SmallTagMap.builder();
builder.addAll(entries);
tagMap = builder.result();
}
/**
* {@inheritDoc}
*/
public Tag getTag(String key) {
return tagMap.get(key);
}
/**
* {@inheritDoc}
*/
public String getValue(String key) {
final Tag t = tagMap.get(key);
return (t == null) ? null : t.getValue();
}
/**
* {@inheritDoc}
*/
public boolean containsKey(String key) {
return tagMap.containsKey(key);
}
/**
* {@inheritDoc}
*/
public boolean isEmpty() {
return tagMap.isEmpty();
}
/**
* {@inheritDoc}
*/
public int size() {
return tagMap.size();
}
/**
* {@inheritDoc}
*/
public Iterator<Tag> iterator() {
return tagMap.iterator();
}
/**
* {@inheritDoc}
*/
public Map<String, String> asMap() {
if (sortedTaglist != null) {
return sortedTaglist;
}
SortedMap<String, String> tagMap = new TreeMap<>();
for (Tag tag : this.tagMap) {
tagMap.put(tag.getKey(), tag.getValue());
}
sortedTaglist = Collections.unmodifiableSortedMap(tagMap);
return sortedTaglist;
}
/**
* Returns a new tag list with additional tags from {@code tags}. If there
* is a conflict with tag keys the tag from {@code tags} will be used.
*/
public BasicTagList copy(TagList tags) {
return concat(this, tags);
}
/**
* Returns a new tag list with an additional tag. If {@code key} is
* already present in this tag list the value will be overwritten with
* {@code value}.
*/
public BasicTagList copy(String key, String value) {
return concat(this, Tags.newTag(key, value));
}
/**
* {@inheritDoc}
*/
@Override
public boolean equals(Object obj) {
return this == obj
|| (obj instanceof BasicTagList) && tagMap.equals(((BasicTagList) obj).tagMap);
}
/**
* {@inheritDoc}
*/
@Override
public int hashCode() {
return tagMap.hashCode();
}
/**
* {@inheritDoc}
*/
@Override
public String toString() {
return Strings.join(",", tagMap.iterator());
}
/**
* Returns a tag list containing the union of {@code t1} and {@code t2}.
* If there is a conflict with tag keys, the tag from {@code t2} will be
* used.
*/
public static BasicTagList concat(TagList t1, TagList t2) {
return new BasicTagList(Iterables.concat(t1, t2));
}
/**
* Returns a tag list containing the union of {@code t1} and {@code t2}.
* If there is a conflict with tag keys, the tag from {@code t2} will be
* used.
*/
public static BasicTagList concat(TagList t1, Tag... t2) {
return new BasicTagList(Iterables.concat(t1, Arrays.asList(t2)));
}
/**
* Returns a tag list from the list of key values passed.
* <p/>
* Example:
* <p/>
* <code>
* BasicTagList tagList = BasicTagList.of("id", "someId", "class", "someClass");
* </code>
*/
public static BasicTagList of(String... tags) {
Preconditions.checkArgument(tags.length % 2 == 0,
"tags must be a sequence of key,value pairs");
final SmallTagMap.Builder builder = SmallTagMap.builder();
for (int i = 0; i < tags.length; i += 2) {
Tag t = Tags.newTag(tags[i], tags[i + 1]);
builder.add(t);
}
return new BasicTagList(builder.result());
}
/**
* Returns a tag list from the tags.
*/
public static BasicTagList of(Tag... tags) {
return new BasicTagList(Arrays.asList(tags));
}
/**
* Returns a tag list that has a copy of {@code tags}.
*
* @deprecated Use {@link #of(Tag...)}
*/
@Deprecated
public static BasicTagList copyOf(Tag... tags) {
return new BasicTagList(Arrays.asList(tags));
}
/**
* Returns a tag list that has a copy of {@code tags}. Each tag value
* is expected to be a string parseable using {@link BasicTag#parseTag}.
*
* @deprecated Use {@link #of(String...)} with separate key, values instead.
*/
@Deprecated
public static BasicTagList copyOf(String... tags) {
return copyOf(Arrays.asList(tags));
}
/**
* Returns a tag list that has a copy of {@code tags}. Each tag value
* is expected to be a string parseable using {@link BasicTag#parseTag}.
*/
public static BasicTagList copyOf(Iterable<String> tags) {
SmallTagMap.Builder builder = SmallTagMap.builder();
for (String tag : tags) {
builder.add(Tags.parseTag(tag));
}
return new BasicTagList(builder.result());
}
/**
* Returns a tag list that has a copy of {@code tags}.
*/
public static BasicTagList copyOf(Map<String, String> tags) {
SmallTagMap.Builder builder = SmallTagMap.builder();
for (Map.Entry<String, String> tag : tags.entrySet()) {
builder.add(Tags.newTag(tag.getKey(), tag.getValue()));
}
return new BasicTagList(builder.result());
}
}