org.wildfly.security.util.StringEnumeration Maven / Gradle / Ivy
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* Copyright 2016 Red Hat, Inc., and individual contributors
* as indicated by the @author tags.
*
* 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 org.wildfly.security.util;
import java.util.HashMap;
import org.wildfly.common.Assert;
/**
* An indexed enumeration of strings. The enumeration can look up string indexes by number, numeric indexes by string,
* or retrieve the interned string value by name.
*
* @author David M. Lloyd
*/
public final class StringEnumeration {
private final HashMap index;
private final Data[] byId;
private StringEnumeration(final HashMap index, final Data[] byId) {
this.index = index;
this.byId = byId;
}
/**
* Construct a new instance. The given values are used as the string members in the order they are given.
*
* @param values the values
* @return the string enumeration
*/
public static StringEnumeration of(String... values) {
final int length = values.length;
Data[] byId = new Data[length];
HashMap index = new HashMap<>(length);
String str;
for (int i = 0; i < length; i ++) {
str = Assert.checkNotNullArrayParam("values", i, values[i]);
index.put(str, byId[i] = new Data(i, str));
}
return new StringEnumeration(index, byId);
}
/**
* Get the canonical name for a string. If the string is not found, an exception is thrown.
*
* @param str the string to look up (must not be {@code null})
* @return the canonical name (not {@code null})
*/
public String canonicalName(String str) {
Assert.checkNotNullParam("str", str);
final Data data = index.get(str);
if (data == null) {
throw ElytronMessages.log.generalInvalidName(str);
}
return data.canonicalName;
}
/**
* Get the numeric index for a string. If the string is not found, an exception is thrown.
*
* @param str the string to look up (must not be {@code null})
* @return the numeric index
*/
public int indexOf(String str) {
Assert.checkNotNullParam("str", str);
final Data data = index.get(str);
if (data == null) {
throw ElytronMessages.log.generalInvalidName(str);
}
return data.index;
}
/**
* Get the canonical name for an index. If the index is out of range, an exception is thrown.
*
* @param index the index to seek
* @return the canonical name (not {@code null})
*/
public String nameOf(int index) {
final Data[] byId = this.byId;
Assert.checkMinimumParameter("index", 0, index);
Assert.checkMaximumParameter("index", size() - 1, index);
return byId[index].canonicalName;
}
/**
* Get the size of this enumeration.
*
* @return the size of this enumeration
*/
public int size() {
return byId.length;
}
static class Data {
final int index;
final String canonicalName;
Data(final int index, final String canonicalName) {
this.index = index;
this.canonicalName = canonicalName;
}
}
}