/*
* Copyright 2016 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.discovery.converters.jackson.builder;
import java.util.HashMap;
import java.util.HashSet;
import java.util.Map;
import java.util.Set;
import com.netflix.appinfo.AmazonInfo;
import com.netflix.appinfo.AmazonInfo.MetaDataKey;
import com.netflix.appinfo.DataCenterInfo.Name;
import com.netflix.discovery.util.StringCache;
/**
* Amazon instance info builder that is doing key names interning, together with
* value interning for selected keys (see {@link StringInterningAmazonInfoBuilder#VALUE_INTERN_KEYS}).
*
* The amount of string objects that is interned here is very limited in scope, and is done by calling
* {@link String#intern()}, with no custom build string cache.
*
* @author Tomasz Bak
*/
public class StringInterningAmazonInfoBuilder {
private static final Set<String> VALUE_INTERN_KEYS;
static {
HashSet<String> keys = new HashSet<>();
keys.add(MetaDataKey.accountId.getName());
keys.add(MetaDataKey.amiId.getName());
keys.add(MetaDataKey.availabilityZone.getName());
keys.add(MetaDataKey.instanceType.getName());
keys.add(MetaDataKey.vpcId.getName());
VALUE_INTERN_KEYS = keys;
}
private HashMap<String, String> metadata;
public StringInterningAmazonInfoBuilder withName(String name) {
return this;
}
public StringInterningAmazonInfoBuilder withMetadata(HashMap<String, String> metadata) {
if (metadata.isEmpty()) {
this.metadata = metadata;
return this;
}
this.metadata = new HashMap<>();
for (Map.Entry<String, String> entry : metadata.entrySet()) {
String key = entry.getKey().intern();
String value = entry.getValue();
if (VALUE_INTERN_KEYS.contains(key)) {
value = StringCache.intern(value);
}
this.metadata.put(key, value);
}
return this;
}
public AmazonInfo build() {
return new AmazonInfo(Name.Amazon.name(), metadata);
}
}