com.google.common.base.CaseFormat Maven / Gradle / Ivy
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This artifact provides a single jar that contains all classes required to use remote EJB and JMS, including
all dependencies. It is intended for use by those not using maven, maven users should just import the EJB and
JMS BOM's instead (shaded JAR's cause lots of problems with maven, as it is very easy to inadvertently end up
with different versions on classes on the class path).
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/*
* Copyright (C) 2006 The Guava Authors
*
* 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.google.common.base;
import static com.google.common.base.Preconditions.checkNotNull;
import static java.util.Objects.requireNonNull;
import com.google.common.annotations.GwtCompatible;
import java.io.Serializable;
import javax.annotation.CheckForNull;
/**
* Utility class for converting between various ASCII case formats. Behavior is undefined for
* non-ASCII input.
*
* @author Mike Bostock
* @since 1.0
*/
@GwtCompatible
@ElementTypesAreNonnullByDefault
public enum CaseFormat {
/** Hyphenated variable naming convention, e.g., "lower-hyphen". */
LOWER_HYPHEN(CharMatcher.is('-'), "-") {
@Override
String normalizeWord(String word) {
return Ascii.toLowerCase(word);
}
@Override
String convert(CaseFormat format, String s) {
if (format == LOWER_UNDERSCORE) {
return s.replace('-', '_');
}
if (format == UPPER_UNDERSCORE) {
return Ascii.toUpperCase(s.replace('-', '_'));
}
return super.convert(format, s);
}
},
/** C++ variable naming convention, e.g., "lower_underscore". */
LOWER_UNDERSCORE(CharMatcher.is('_'), "_") {
@Override
String normalizeWord(String word) {
return Ascii.toLowerCase(word);
}
@Override
String convert(CaseFormat format, String s) {
if (format == LOWER_HYPHEN) {
return s.replace('_', '-');
}
if (format == UPPER_UNDERSCORE) {
return Ascii.toUpperCase(s);
}
return super.convert(format, s);
}
},
/** Java variable naming convention, e.g., "lowerCamel". */
LOWER_CAMEL(CharMatcher.inRange('A', 'Z'), "") {
@Override
String normalizeWord(String word) {
return firstCharOnlyToUpper(word);
}
@Override
String normalizeFirstWord(String word) {
return Ascii.toLowerCase(word);
}
},
/** Java and C++ class naming convention, e.g., "UpperCamel". */
UPPER_CAMEL(CharMatcher.inRange('A', 'Z'), "") {
@Override
String normalizeWord(String word) {
return firstCharOnlyToUpper(word);
}
},
/** Java and C++ constant naming convention, e.g., "UPPER_UNDERSCORE". */
UPPER_UNDERSCORE(CharMatcher.is('_'), "_") {
@Override
String normalizeWord(String word) {
return Ascii.toUpperCase(word);
}
@Override
String convert(CaseFormat format, String s) {
if (format == LOWER_HYPHEN) {
return Ascii.toLowerCase(s.replace('_', '-'));
}
if (format == LOWER_UNDERSCORE) {
return Ascii.toLowerCase(s);
}
return super.convert(format, s);
}
};
private final CharMatcher wordBoundary;
private final String wordSeparator;
CaseFormat(CharMatcher wordBoundary, String wordSeparator) {
this.wordBoundary = wordBoundary;
this.wordSeparator = wordSeparator;
}
/**
* Converts the specified {@code String str} from this format to the specified {@code format}. A
* "best effort" approach is taken; if {@code str} does not conform to the assumed format, then
* the behavior of this method is undefined but we make a reasonable effort at converting anyway.
*/
public final String to(CaseFormat format, String str) {
checkNotNull(format);
checkNotNull(str);
return (format == this) ? str : convert(format, str);
}
/** Enum values can override for performance reasons. */
String convert(CaseFormat format, String s) {
// deal with camel conversion
StringBuilder out = null;
int i = 0;
int j = -1;
while ((j = wordBoundary.indexIn(s, ++j)) != -1) {
if (i == 0) {
// include some extra space for separators
out = new StringBuilder(s.length() + 4 * format.wordSeparator.length());
out.append(format.normalizeFirstWord(s.substring(i, j)));
} else {
requireNonNull(out).append(format.normalizeWord(s.substring(i, j)));
}
out.append(format.wordSeparator);
i = j + wordSeparator.length();
}
return (i == 0)
? format.normalizeFirstWord(s)
: requireNonNull(out).append(format.normalizeWord(s.substring(i))).toString();
}
/**
* Returns a serializable {@code Converter} that converts strings from this format to {@code
* targetFormat}.
*
* @since 16.0
*/
public Converter converterTo(CaseFormat targetFormat) {
return new StringConverter(this, targetFormat);
}
private static final class StringConverter extends Converter
implements Serializable {
private final CaseFormat sourceFormat;
private final CaseFormat targetFormat;
StringConverter(CaseFormat sourceFormat, CaseFormat targetFormat) {
this.sourceFormat = checkNotNull(sourceFormat);
this.targetFormat = checkNotNull(targetFormat);
}
@Override
protected String doForward(String s) {
return sourceFormat.to(targetFormat, s);
}
@Override
protected String doBackward(String s) {
return targetFormat.to(sourceFormat, s);
}
@Override
public boolean equals(@CheckForNull Object object) {
if (object instanceof StringConverter) {
StringConverter that = (StringConverter) object;
return sourceFormat.equals(that.sourceFormat) && targetFormat.equals(that.targetFormat);
}
return false;
}
@Override
public int hashCode() {
return sourceFormat.hashCode() ^ targetFormat.hashCode();
}
@Override
public String toString() {
return sourceFormat + ".converterTo(" + targetFormat + ")";
}
private static final long serialVersionUID = 0L;
}
abstract String normalizeWord(String word);
String normalizeFirstWord(String word) {
return normalizeWord(word);
}
private static String firstCharOnlyToUpper(String word) {
return word.isEmpty()
? word
: Ascii.toUpperCase(word.charAt(0)) + Ascii.toLowerCase(word.substring(1));
}
}