org.openrewrite.internal.StringUtils Maven / Gradle / Ivy
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/*
* Copyright 2020 the original author or 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
*
* https://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.openrewrite.internal;
import org.jspecify.annotations.NonNull;
import org.jspecify.annotations.Nullable;
import java.io.ByteArrayOutputStream;
import java.io.File;
import java.io.IOException;
import java.io.InputStream;
import java.nio.charset.Charset;
import java.nio.charset.StandardCharsets;
import java.util.Arrays;
import java.util.function.Predicate;
import java.util.regex.Pattern;
public class StringUtils {
private static final Pattern LINE_BREAK = Pattern.compile("\\R");
private StringUtils() {
}
public static @Nullable String trimIndentPreserveCRLF(@Nullable String text) {
if (text == null) {
//noinspection DataFlowIssue
return null;
}
return trimIndent((text.endsWith("\r\n") ? text.substring(0, text.length() - 2) : text)
.replace('\r', '⏎'))
.replace('⏎', '\r');
}
/**
* Detects a common minimal indent of all the input lines and removes the indent from each line.
*
* This is modeled after Kotlin's trimIndent and is useful for pruning the indent from multi-line text blocks.
*
* Note: Blank lines do not affect the detected indent level.
*
* @param text A string that have a common indention
* @return A mutated version of the string that removed the common indention.
*/
public static String trimIndent(String text) {
if (text.isEmpty()) {
return text;
}
int indentLevel = minCommonIndentLevel(text);
// The logic for trimming the start of the string is consistent with the functionality of Kotlin's trimIndent.
char startChar = text.charAt(0);
int start = 0;
if (startChar == '\n' || startChar == '\r') {
//If the string starts with a line break, always trim it.
int i = 1;
for (; i < text.length(); i++) {
char c = text.charAt(i);
if (!Character.isWhitespace(c)) {
//If there is any non-whitespace on the first line, do not trim the line.
start = 1;
break;
} else if (c == '\n' || c == '\r') {
if (i - 1 <= indentLevel) {
//If the first line is only whitespace and the line size is less than indent size, trim it.
start = i;
} else {
//If the line size is equal or greater than indent, do not trim the line.
start = 1;
}
break;
}
}
}
//If the last line of the string is only whitespace, trim it.
int end = text.length() - 1;
while (end > start) {
char endChar = text.charAt(end);
if (!Character.isWhitespace(endChar)) {
end = text.length();
break;
} else if (endChar == '\n' || endChar == '\r') {
break;
}
end--;
}
if (end == start) {
end++;
}
StringBuilder trimmed = new StringBuilder();
for (int i = start; i < end; i++) {
int j = i;
for (; j < end; j++) {
char c = text.charAt(j);
if (c == '\r' || c == '\n') {
trimmed.append(c);
break;
}
if (j - i >= indentLevel) {
trimmed.append(c);
}
}
i = j;
}
return trimmed.toString();
}
/**
* This method will count the number of white space characters that precede any content for each line contained
* in string. It will not compute a white space count for a line, if the entire line is blank (only made up of white
* space characters).
*
* It will compute the minimum common number of white spaces across all lines and return that minimum.
*
* @param text A string with zero or more line breaks.
* @return The minimum count of white space characters preceding each line of content.
*/
public static int minCommonIndentLevel(String text) {
int minIndent = Integer.MAX_VALUE;
int whiteSpaceCount = 0;
boolean contentEncountered = false;
for (int i = 0; i < text.length(); i++) {
char c = text.charAt(i);
if (c == '\n' || c == '\r') {
if (contentEncountered) {
minIndent = Math.min(whiteSpaceCount, minIndent);
if (minIndent == 0) {
break;
}
}
whiteSpaceCount = 0;
contentEncountered = false;
} else if (!contentEncountered && Character.isWhitespace(c)) {
whiteSpaceCount++;
} else {
contentEncountered = true;
}
}
if (contentEncountered) {
minIndent = Math.min(whiteSpaceCount, minIndent);
}
return minIndent;
}
/**
* Check if the String is null or has only whitespaces.
*
* Modified from apache commons lang StringUtils.
*
* @param string String to check
* @return {@code true} if the String is null or has only whitespaces
*/
public static boolean isBlank(@Nullable String string) {
if (string == null || string.isEmpty()) {
return true;
}
for (int i = 0; i < string.length(); i++) {
if (!Character.isWhitespace(string.charAt(i))) {
return false;
}
}
return true;
}
/**
* Check if the String is empty string or null.
*
* @param string String to check
* @return {@code true} if the String is null or empty string
*/
public static boolean isNullOrEmpty(@Nullable String string) {
return string == null || string.isEmpty();
}
public static boolean isNotEmpty(@Nullable String string) {
return string != null && !string.isEmpty();
}
public static String readFully(@Nullable InputStream inputStream) {
if (inputStream == null) {
return "";
}
return readFully(inputStream, StandardCharsets.UTF_8);
}
/**
* If the input stream is coming from a stream with an unknown encoding, use
* {@link EncodingDetectingInputStream#readFully()} instead.
*
* @param inputStream An input stream.
* @return the full contents of the input stream interpreted as a string of the specified encoding
*/
public static String readFully(InputStream inputStream, Charset charset) {
try (InputStream is = inputStream) {
ByteArrayOutputStream bos = new ByteArrayOutputStream();
byte[] buffer = new byte[4096];
int n;
while ((n = is.read(buffer)) != -1) {
bos.write(buffer, 0, n);
}
byte[] bytes = bos.toByteArray();
return new String(bytes, charset);
} catch (IOException e) {
throw new UnsupportedOperationException(e);
}
}
public static String capitalize(String value) {
if (value.isEmpty()) {
return value;
}
return Character.toUpperCase(value.charAt(0)) +
value.substring(1);
}
public static String uncapitalize(String value) {
if (value.isEmpty()) {
return value;
}
return Character.toLowerCase(value.charAt(0)) + value.substring(1);
}
public static boolean containsOnlyWhitespaceAndComments(String text) {
int i = 0;
char[] chars = text.toCharArray();
boolean inSingleLineComment = false;
boolean inMultilineComment = false;
while (i < chars.length) {
char c = chars[i];
if (inSingleLineComment && c == '\n') {
inSingleLineComment = false;
continue;
}
if (i < chars.length - 1) {
String s = String.valueOf(c) + chars[i + 1];
switch (s) {
case "//": {
inSingleLineComment = true;
i += 2;
continue;
}
case "/*": {
inMultilineComment = true;
i += 2;
continue;
}
case "*/": {
inMultilineComment = false;
i += 2;
continue;
}
}
}
if (!inSingleLineComment && !inMultilineComment && !Character.isWhitespace(c)) {
return false;
}
i++;
}
return true;
}
public static int indexOfNonWhitespace(String text) {
for (int i = 0; i < text.length(); i++) {
char c = text.charAt(i);
if (!(c == ' ' || c == '\t' || c == '\n' || c == '\r')) {
return i;
}
}
return -1;
}
/**
* @param text Text to scan
* @param test The predicate to match
* @return The index of the first character for which the predicate returns true
,
* or -1
if no character in the string matches the predicate.
*/
public static int indexOf(String text, Predicate test) {
for (int i = 0; i < text.length(); i++) {
if (test.test(text.charAt(i))) {
return i;
}
}
return -1;
}
/**
* Return the number of times a substring occurs within a target string.
*
* @param text A target string
* @param substring The substring to search for
* @return the number of times the substring is found in the target. 0 if no occurrences are found.
*/
public static int countOccurrences(@NonNull String text, @NonNull String substring) {
if (text.isEmpty() || substring.isEmpty()) {
return 0;
}
int count = 0;
for (int index = text.indexOf(substring); index >= 0; index = text.indexOf(substring, index + substring.length())) {
count++;
}
return count;
}
/**
* This method will search and replace the first occurrence of a matching substring. There is a a replaceFirst method
* on the String class but that version leverages regular expressions and is a magnitude slower than this simple
* replacement.
*
* @param text The source string to search
* @param match The substring that is being searched for
* @param replacement The replacement.
* @return The original string with the first occurrence replaced or the original text if a match is not found.
*/
public static String replaceFirst(@NonNull String text, @NonNull String match, @NonNull String replacement) {
int start = text.indexOf(match);
if (match.isEmpty() || text.isEmpty() || start == -1) {
return text;
} else {
StringBuilder newValue = new StringBuilder(text.length());
newValue.append(text, 0, start);
newValue.append(replacement);
int end = start + match.length();
if (end < text.length()) {
newValue.append(text, end, text.length());
}
return newValue.toString();
}
}
public static String repeat(String s, int count) {
if (count == 1) {
return s;
}
byte[] value = s.getBytes();
int len = value.length;
if (len == 0 || count == 0) {
return "";
}
if (len == 1) {
final byte[] single = new byte[count];
Arrays.fill(single, value[0]);
return new String(single);
}
int limit = len * count;
byte[] multiple = new byte[limit];
System.arraycopy(value, 0, multiple, 0, len);
int copied = len;
for (; copied < limit - copied; copied <<= 1) {
System.arraycopy(multiple, 0, multiple, copied, copied);
}
System.arraycopy(multiple, 0, multiple, copied, limit - copied);
return new String(multiple);
}
public static boolean matchesGlob(@Nullable String value, @Nullable String globPattern) {
if ("*".equals(globPattern)) {
return true;
}
if (globPattern == null) {
return false;
}
if (value == null) {
value = "";
}
return matchesGlob(
globPattern.replace(wrongFileSeparatorChar, File.separatorChar),
value.replace(wrongFileSeparatorChar, File.separatorChar),
false
);
}
private static final char wrongFileSeparatorChar = File.separatorChar == '/' ? '\\' : '/';
private static boolean matchesGlob(String pattern, String str, boolean caseSensitive) {
int patIdxStart = 0;
int patIdxEnd = pattern.length() - 1;
int strIdxStart = 0;
int strIdxEnd = str.length() - 1;
if (!pattern.contains("*")) {
// No '*'s, so we make a shortcut
if (patIdxEnd != strIdxEnd) {
return false; // Pattern and string do not have the same size
}
for (int i = 0; i <= patIdxEnd; i++) {
char ch = pattern.charAt(i);
if (ch != '?' && different(caseSensitive, ch, str.charAt(i))) {
return false; // Character mismatch
}
}
return true; // String matches against pattern
}
if (patIdxEnd == 0) {
return true; // Pattern contains only '*', which matches anything
}
// Process characters before first star
while (patIdxStart <= patIdxEnd && strIdxStart <= strIdxEnd) {
char ch = pattern.charAt(patIdxStart);
if (ch == '*') {
break;
}
if (ch != '?' &&
different(caseSensitive, ch, str.charAt(strIdxStart))) {
return false; // Character mismatch
}
patIdxStart++;
strIdxStart++;
}
if (strIdxStart > strIdxEnd) {
// All characters in the string are used. Check if only '*'s are
// left in the pattern. If so, we succeeded. Otherwise failure.
return allStars(pattern, patIdxStart, patIdxEnd);
} else if (patIdxStart > patIdxEnd) {
// String not exhausted by pattern is. Failure
return false;
}
// Process characters after last star
while (patIdxStart <= patIdxEnd && strIdxStart <= strIdxEnd) {
char ch = pattern.charAt(patIdxEnd);
if (ch == '*') {
break;
}
if (ch != '?' && different(caseSensitive, ch, str.charAt(strIdxEnd))) {
return false; // Character mismatch
}
patIdxEnd--;
strIdxEnd--;
}
if (strIdxStart > strIdxEnd) {
// All characters in the string are used. Check if only '*'s are
// left in the pattern. If so, we succeeded. Otherwise failure.
return allStars(pattern, patIdxStart, patIdxEnd);
}
// process pattern between stars. padIdxStart and patIdxEnd point
// always to a '*'.
while (patIdxStart != patIdxEnd && strIdxStart <= strIdxEnd) {
int patIdxTmp = -1;
for (int i = patIdxStart + 1; i <= patIdxEnd; i++) {
if (pattern.charAt(i) == '*') {
patIdxTmp = i;
break;
}
}
if (patIdxTmp == patIdxStart + 1) {
// Two stars next to each other, skip the first one.
patIdxStart++;
continue;
}
// Find the pattern between padIdxStart & padIdxTmp in str between
// strIdxStart & strIdxEnd
int patLength = (patIdxTmp - patIdxStart - 1);
int strLength = (strIdxEnd - strIdxStart + 1);
int foundIdx = -1;
strLoop:
for (int i = 0; i <= strLength - patLength; i++) {
for (int j = 0; j < patLength; j++) {
char ch = pattern.charAt(patIdxStart + j + 1);
if (ch != '?' && different(caseSensitive, ch, str.charAt(strIdxStart + i + j))) {
continue strLoop;
}
}
foundIdx = strIdxStart + i;
break;
}
if (foundIdx == -1) {
return false;
}
patIdxStart = patIdxTmp;
strIdxStart = foundIdx + patLength;
}
// All characters in the string are used. Check if only '*'s are left
// in the pattern. If so, we succeeded. Otherwise failure.
return allStars(pattern, patIdxStart, patIdxEnd);
}
private static boolean allStars(String chars, int start, int end) {
for (int i = start; i <= end; ++i) {
if (chars.charAt(i) != '*') {
return false;
}
}
return true;
}
private static boolean different(boolean caseSensitive, char ch, char other) {
return caseSensitive ?
ch != other :
Character.toUpperCase(ch) != Character.toUpperCase(other);
}
public static String indent(String text) {
StringBuilder indent = new StringBuilder();
for (int i = 0; i < text.length(); i++) {
char c = text.charAt(i);
if (c == '\n' || c == '\r') {
return indent.toString();
} else if (Character.isWhitespace(c)) {
indent.append(c);
} else {
return indent.toString();
}
}
return indent.toString();
}
/**
* Locate the greatest common margin of a multi-line string
*
* @param multiline A string of one or more lines.
* @return The greatest common margin consisting only of whitespace characters.
*/
public static String greatestCommonMargin(String multiline) {
String gcm = null;
StringBuilder margin = new StringBuilder();
boolean skipRestOfLine = false;
char[] charArray = multiline.toCharArray();
for (int i = 0; i < charArray.length; i++) {
char c = charArray[i];
if (c == '\n') {
if (i < charArray.length - 1 && charArray[i + 1] == '\n') {
i++;
continue;
} else if (i > 0) {
if (margin.length() == 0) {
return "";
} else {
gcm = commonMargin(gcm, margin);
margin = new StringBuilder();
}
}
skipRestOfLine = false;
} else if (Character.isWhitespace(c) && !skipRestOfLine) {
margin.append(c);
} else {
skipRestOfLine = true;
}
}
return gcm == null ? "" : gcm;
}
public static String commonMargin(@Nullable CharSequence s1, CharSequence s2) {
if (s1 == null) {
String s = s2.toString();
return s.substring(s.lastIndexOf('\n') + 1);
}
for (int i = 0; i < s1.length() && i < s2.length(); i++) {
if (s1.charAt(i) != s2.charAt(i) || !Character.isWhitespace(s1.charAt(i))) {
return s1.toString().substring(0, i);
}
}
return s2.length() < s1.length() ? s2.toString() : s1.toString();
}
public static boolean isNumeric(@Nullable String str) {
if (str == null || str.isEmpty()) {
return false;
}
int sz = str.length();
for (int i = 0; i < sz; i++) {
if (!Character.isDigit(str.charAt(i))) {
return false;
}
}
return true;
}
/**
* See https://eclipse.org/aspectj/doc/next/progguide/semantics-pointcuts.html#type-patterns
*
* An embedded * in an identifier matches any sequence of characters, but
* does not match the package (or inner-type) separator ".".
*
* The ".." wildcard matches any sequence of characters that start and end with a ".", so it can be used to pick out all
* types in any subpackage, or all inner types. e.g. within(com.xerox..*)
picks out all join points where
* the code is in any declaration of a type whose name begins with "com.xerox.".
*/
public static String aspectjNameToPattern(String name) {
int length = name.length();
StringBuilder sb = new StringBuilder(length);
char prev = 0;
for (int i = 0; i < length; i++) {
boolean isLast = i == length - 1;
char c = name.charAt(i);
switch (c) {
case '.':
if (prev != '.' && (isLast || name.charAt(i + 1) != '.')) {
sb.append("[.$]");
} else if (prev == '.') {
sb.append("\\.(.+\\.)?");
}
break;
case '*':
sb.append("[^.]*");
break;
case '$':
case '[':
case ']':
sb.append('\\');
// fall-through
default:
sb.append(c);
}
prev = c;
}
return sb.toString();
}
/**
* @param s1 first string
* @param s2 second string
* @return length of the longest substring common to both strings
* @see
*/
public static int greatestCommonSubstringLength(String s1, String s2) {
if (s1.isEmpty() || s2.isEmpty()) {
return 0;
}
int m = s1.length();
int n = s2.length();
int cost;
int maxLen = 0;
int[] p = new int[n];
int[] d = new int[n];
for (int i = 0; i < m; ++i) {
for (int j = 0; j < n; ++j) {
// calculate cost/score
if (s1.charAt(i) != s2.charAt(j)) {
cost = 0;
} else {
if ((i == 0) || (j == 0)) {
cost = 1;
} else {
cost = p[j - 1] + 1;
}
}
d[j] = cost;
if (cost > maxLen) {
maxLen = cost;
}
} // for {}
int[] swap = p;
p = d;
d = swap;
}
return maxLen;
}
/**
* @return Considering C-style comments to be whitespace, return the index of the next non-whitespace character.
*/
public static int indexOfNextNonWhitespace(int cursor, String source) {
boolean inMultiLineComment = false;
boolean inSingleLineComment = false;
int length = source.length();
for (; cursor < length; cursor++) {
char current = source.charAt(cursor);
if (inSingleLineComment) {
inSingleLineComment = current != '\n';
continue;
} else if (length > cursor + 1) {
char next = source.charAt(cursor + 1);
if (current == '/' && next == '/') {
inSingleLineComment = true;
cursor++;
continue;
} else if (current == '/' && next == '*') {
inMultiLineComment = true;
cursor++;
continue;
} else if (current == '*' && next == '/') {
inMultiLineComment = false;
cursor++;
continue;
}
}
if (!inMultiLineComment && !Character.isWhitespace(current)) {
break; // found it!
}
}
return cursor;
}
public static String formatUriForPropertiesFile(String uri) {
return uri.replaceAll("(?