// Copyright 2014 The Bazel Authors. All rights reserved. // // 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.devtools.build.lib.util; import com.google.common.base.Joiner; import com.google.common.base.Preconditions; import com.google.common.collect.Iterables; import java.util.Collection; import java.util.Iterator; /** * Various utility methods operating on strings. */ public class StringUtil { /** * Creates a comma-separated list of words as in English. * *
Example: ["a", "b", "c"] -> "a, b or c". */ public static String joinEnglishList(Iterable> choices) { return joinEnglishList(choices, "or", ""); } /** * Creates a comma-separated list of words as in English with the given last-separator. * *
Example with lastSeparator="then": ["a", "b", "c"] -> "a, b then c". */ public static String joinEnglishList(Iterable> choices, String lastSeparator) { return joinEnglishList(choices, lastSeparator, ""); } /** * Creates a comma-separated list of words as in English with the given last-separator and quotes. * *
Example with lastSeparator="then", quote="'": ["a", "b", "c"] -> "'a', 'b' then 'c'".
*/
public static String joinEnglishList(Iterable> choices, String lastSeparator, String quote) {
StringBuilder buf = new StringBuilder();
for (Iterator> ii = choices.iterator(); ii.hasNext(); ) {
Object choice = ii.next();
if (buf.length() > 0) {
buf.append(ii.hasNext() ? "," : " " + lastSeparator);
buf.append(" ");
}
buf.append(quote).append(choice).append(quote);
}
return buf.length() == 0 ? "nothing" : buf.toString();
}
/**
* Lists items up to a given limit, then prints how many were omitted.
*/
public static StringBuilder listItemsWithLimit(StringBuilder appendTo, int limit,
Collection> items) {
Preconditions.checkState(limit > 0);
Joiner.on(", ").appendTo(appendTo, Iterables.limit(items, limit));
if (items.size() > limit) {
appendTo.append(" ...(omitting ")
.append(items.size() - limit)
.append(" more item(s))");
}
return appendTo;
}
/**
* Returns the ordinal representation of the number.
*/
public static String ordinal(int number) {
switch (number) {
case 1:
return "1st";
case 2:
return "2nd";
case 3:
return "3rd";
default:
return number + "th";
}
}
/**
* Appends a prefix and a suffix to each of the Strings.
*/
public static Iterable The beginning of the string before the first newline is not indented.
*/
public static String indent(String input, int depth) {
StringBuilder prefix = new StringBuilder();
prefix.append("\n");
for (int i = 0; i < depth; i++) {
prefix.append(" ");
}
return input.replace("\n", prefix);
}
/**
* Strips a suffix from a string. If the string does not end with the suffix, returns null.
*/
public static String stripSuffix(String input, String suffix) {
return input.endsWith(suffix)
? input.substring(0, input.length() - suffix.length())
: null;
}
/**
* Capitalizes the first character of a string.
*/
public static String capitalize(String input) {
if (input.isEmpty()) {
return input;
}
char first = input.charAt(0);
char capitalized = Character.toUpperCase(first);
return first == capitalized ? input : capitalized + input.substring(1);
}
}