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strman-java/src/main/java/strman/Strman.java
T

921 lines
33 KiB
Java

package strman;
import java.util.*;
import java.util.function.BiFunction;
import java.util.function.Predicate;
import java.util.function.Supplier;
import java.util.regex.Matcher;
import java.util.regex.Pattern;
import java.util.stream.Stream;
import static java.util.stream.Collectors.joining;
/**
* A String manipulation library without any dependencies
*/
public abstract class Strman {
private static final Predicate<String> NULL_STRING_PREDICATE = str -> str == null;
private static final Supplier<String> NULL_STRING_MSG_SUPPLIER = () -> "'value' should be not null.";
private Strman() {
}
/**
* Appends Strings to value
*
* @param value initial String
* @param appends an array of strings to append
* @return full String
*/
public static String append(final String value, final String... appends) {
return appendArray(value, appends);
}
/**
* Append an array of String to value
*
* @param value initial String
* @param appends an array of strings to append
* @return full String
*/
public static String appendArray(final String value, final String[] appends) {
validate(value, NULL_STRING_PREDICATE, NULL_STRING_MSG_SUPPLIER);
if (appends == null || appends.length == 0) {
return value;
}
StringJoiner joiner = new StringJoiner("");
for (String append : appends) {
joiner.add(append);
}
return value + joiner.toString();
}
/**
* Get the character at index. This method will take care of negative indexes.
* The valid value of index is between -(length-1) to (length-1).
* For values which don't fall under this range Optional.empty will be returned.
*
* @param value input value
* @param index location
* @return an Optional String if found else empty
*/
public static Optional<String> at(final String value, int index) {
if (value == null || value.isEmpty()) {
return Optional.empty();
}
int length = value.length();
if (index < 0) {
index = length + index;
}
return (index < length && index >= 0) ? Optional.of(String.valueOf(value.charAt(index))) : Optional.empty();
}
/**
* Returns an array with strings between start and end.
*
* @param value input
* @param start start
* @param end end
* @return Array containing different parts between start and end.
*/
public static String[] between(final String value, final String start, final String end) {
validate(value, NULL_STRING_PREDICATE, NULL_STRING_MSG_SUPPLIER);
validate(start, NULL_STRING_PREDICATE, () -> "'start' should be not null.");
validate(end, NULL_STRING_PREDICATE, () -> "'end' should be not null.");
String[] parts = value.split(end);
return Arrays.stream(parts).map(subPart -> subPart.substring(subPart.indexOf(start) + start.length())).toArray(String[]::new);
}
/**
* Returns a String array consisting of the characters in the String.
*
* @param value input
* @return character array
*/
public static String[] chars(final String value) {
/**
* The other implementation of this could be using String's split method
* String[] chars = value.split("")
*/
validate(value, NULL_STRING_PREDICATE, NULL_STRING_MSG_SUPPLIER);
int length = value.length();
String[] result = new String[length];
for (int i = 0; i < length; i++) {
result[i] = at(value, i).get();
}
return result;
}
/**
* Replace consecutive whitespace characters with a single space.
*
* @param value input String
* @return collapsed String
*/
public static String collapseWhitespace(final String value) {
validate(value, NULL_STRING_PREDICATE, NULL_STRING_MSG_SUPPLIER);
return value.trim().replaceAll("\\s\\s+", " ");
}
/**
* Verifies that the needle is contained in the value. The search is case insensitive
*
* @param value to search
* @param needle to find
* @return true if found else false.
*/
public static boolean contains(final String value, final String needle) {
return contains(value, needle, false);
}
/**
* Verifies that the needle is contained in the value.
*
* @param value to search
* @param needle to find
* @param caseSensitive true or false
* @return true if found else false.
*/
public static boolean contains(final String value, final String needle, final boolean caseSensitive) {
validate(value, NULL_STRING_PREDICATE, NULL_STRING_MSG_SUPPLIER);
if (caseSensitive) {
return value.contains(needle);
}
return value.toLowerCase().contains(needle.toLowerCase());
}
/**
* Verifies that all needles are contained in value. The search is case insensitive
*
* @param value input String to search
* @param needles needles to find
* @return true if all needles are found else false.
*/
public static boolean containsAll(final String value, final String[] needles) {
validate(value, NULL_STRING_PREDICATE, NULL_STRING_MSG_SUPPLIER);
return Arrays.stream(needles).allMatch(needle -> contains(value, needle, false));
}
/**
* Verifies that all needles are contained in value
*
* @param value input String to search
* @param needles needles to find
* @param caseSensitive true or false
* @return true if all needles are found else false.
*/
public static boolean containsAll(final String value, final String[] needles, final boolean caseSensitive) {
validate(value, NULL_STRING_PREDICATE, NULL_STRING_MSG_SUPPLIER);
return Arrays.stream(needles).allMatch(needle -> contains(value, needle, caseSensitive));
}
/**
* Verifies that one or more of needles are contained in value. This is case insensitive
*
* @param value input
* @param needles needles to search
* @return boolean true if any needle is found else false
*/
public static boolean containsAny(final String value, final String[] needles) {
return containsAny(value, needles, false);
}
/**
* Verifies that one or more of needles are contained in value.
*
* @param value input
* @param needles needles to search
* @param caseSensitive true or false
* @return boolean true if any needle is found else false
*/
public static boolean containsAny(final String value, final String[] needles, final boolean caseSensitive) {
validate(value, NULL_STRING_PREDICATE, NULL_STRING_MSG_SUPPLIER);
return Arrays.stream(needles).anyMatch(needle -> contains(value, needle, caseSensitive));
}
/**
* Count the number of times substr appears in value
*
* @param value input
* @param subStr to search
* @return count of times substring exists
*/
public static long countSubstr(final String value, final String subStr) {
return countSubstr(value, subStr, false, false);
}
/**
* Count the number of times substr appears in value
*
* @param value input
* @param subStr search string
* @param caseSensitive whether search should be case sensitive
* @param allowOverlapping boolean to take into account overlapping
* @return count of times substring exists
*/
public static long countSubstr(final String value, final String subStr, final boolean caseSensitive, boolean allowOverlapping) {
validate(value, NULL_STRING_PREDICATE, NULL_STRING_MSG_SUPPLIER);
return countSubstr(caseSensitive ? value : value.toLowerCase(), caseSensitive ? subStr : subStr.toLowerCase(), allowOverlapping, 0L);
}
/**
* Test if value ends with search. The search is case sensitive.
*
* @param value input string
* @param search string to search
* @return true or false
*/
public static boolean endsWith(final String value, final String search) {
validate(value, NULL_STRING_PREDICATE, NULL_STRING_MSG_SUPPLIER);
return endsWith(value, search, value.length(), true);
}
/**
* Test if value ends with search.
*
* @param value input string
* @param search string to search
* @param caseSensitive true or false
* @return true or false
*/
public static boolean endsWith(final String value, final String search, final boolean caseSensitive) {
validate(value, NULL_STRING_PREDICATE, NULL_STRING_MSG_SUPPLIER);
return endsWith(value, search, value.length(), caseSensitive);
}
/**
* Test if value ends with search.
*
* @param value input string
* @param search string to search
* @param position position till which you want to search.
* @param caseSensitive true or false
* @return true or false
*/
public static boolean endsWith(final String value, final String search, final int position, final boolean caseSensitive) {
validate(value, NULL_STRING_PREDICATE, NULL_STRING_MSG_SUPPLIER);
int remainingLength = position - search.length();
if (caseSensitive) {
return value.indexOf(search, remainingLength) > -1;
}
return value.toLowerCase().indexOf(search.toLowerCase(), remainingLength) > -1;
}
/**
* Ensures that the value begins with prefix. If it doesn't exist, it's prepended. It is case sensitive.
*
* @param value input
* @param prefix prefix
* @return string with prefix if it was not present.
*/
public static String ensureLeft(final String value, final String prefix) {
return ensureLeft(value, prefix, true);
}
/**
* Ensures that the value begins with prefix. If it doesn't exist, it's prepended.
*
* @param value input
* @param prefix prefix
* @param caseSensitive true or false
* @return string with prefix if it was not present.
*/
public static String ensureLeft(final String value, final String prefix, final boolean caseSensitive) {
validate(value, NULL_STRING_PREDICATE, NULL_STRING_MSG_SUPPLIER);
if (caseSensitive) {
return value.startsWith(prefix) ? value : prefix + value;
}
String _value = value.toLowerCase();
String _prefix = prefix.toLowerCase();
return _value.startsWith(_prefix) ? value : prefix + value;
}
/**
* Decodes data encoded with MIME base64
*
* @param value The data to decode
* @return decoded data
*/
public static String base64Decode(final String value) {
validate(value, NULL_STRING_PREDICATE, NULL_STRING_MSG_SUPPLIER);
return new String(Base64.getDecoder().decode(value));
}
/**
* Encodes data with MIME base64.
*
* @param value The data to encode
* @return The encoded String
*/
public static String base64Encode(final String value) {
validate(value, NULL_STRING_PREDICATE, NULL_STRING_MSG_SUPPLIER);
return Base64.getEncoder().encodeToString(value.getBytes());
}
/**
* Convert binary unicode (16 digits) string to string chars
*
* @param value The value to decode
* @return The decoded String
*/
public static String binDecode(final String value) {
return decode(value, 16, 2);
}
/**
* Convert string chars to binary unicode (16 digits)
*
* @param value The value to encode
* @return String in binary format
*/
public static String binEncode(final String value) {
return encode(value, 16, 2);
}
/**
* Convert decimal unicode (5 digits) string to string chars
*
* @param value The value to decode
* @return decoded String
*/
public static String decDecode(final String value) {
return decode(value, 5, 10);
}
/**
* Convert string chars to decimal unicode (5 digits)
*
* @param value The value to encode
* @return Encoded value
*/
public static String decEncode(final String value) {
return encode(value, 5, 10);
}
/**
* Ensures that the value ends with suffix. If it doesn't, it's appended. This operation is case sensitive.
*
* @param value The input String
* @param suffix The substr to be ensured to be right
* @return The string which is guarenteed to start with substr
*/
public static String ensureRight(final String value, final String suffix) {
return ensureRight(value, suffix, true);
}
/**
* Ensures that the value ends with suffix. If it doesn't, it's appended.
*
* @param value The input String
* @param suffix The substr to be ensured to be right
* @param caseSensitive Use case (in-)sensitive matching for determining if value already ends with suffix
* @return The string which is guarenteed to start with substr
*/
public static String ensureRight(final String value, final String suffix, boolean caseSensitive) {
validate(value, NULL_STRING_PREDICATE, NULL_STRING_MSG_SUPPLIER);
return endsWith(value, suffix, caseSensitive) ? value : append(value, suffix);
}
/**
* Returns the first n chars of String
*
* @param value The input String
* @param n Number of chars to return
* @return The first n chars
*/
public static String first(final String value, final int n) {
validate(value, NULL_STRING_PREDICATE, NULL_STRING_MSG_SUPPLIER);
return value.substring(0, n);
}
/**
* Return the first char of String
*
* @param value The input String
* @return The first char
*/
public static String head(final String value) {
return first(value, 1);
}
/**
* Formats a string using parameters
*
* @param value The value to be formatted
* @param params Parameters to be described in the string
* @return The formatted string
*/
public static String format(final String value, String... params) {
validate(value, NULL_STRING_PREDICATE, NULL_STRING_MSG_SUPPLIER);
Pattern p = Pattern.compile("\\{(\\w+)\\}");
Matcher m = p.matcher(value);
String result = value;
while (m.find()) {
int paramNumber = Integer.parseInt(m.group(1));
if (params == null || paramNumber >= params.length) {
throw new IllegalArgumentException("params does not have value for " + m.group());
}
result = result.replace(m.group(), params[paramNumber]);
}
return result;
}
/**
* Convert hexadecimal unicode (4 digits) string to string chars
*
* @param value The value to decode
* @return The decoded String
*/
public static String hexDecode(final String value) {
return decode(value, 4, 16);
}
/**
* Convert string chars to hexadecimal unicode (4 digits)
*
* @param value The value to encode
* @return String in hexadecimal format.
*/
public static String hexEncode(final String value) {
return encode(value, 4, 16);
}
/**
* The indexOf() method returns the index within the calling String of the first occurrence of the specified value, starting the search at fromIndex.
* Returns -1 if the value is not found.
*
* @param value The input String
* @param needle The search String
* @param offset The offset to start searching from.
* @param caseSensitive boolean to indicate whether search should be case sensitive
* @return Returns position of first occurrence of needle.
*/
public static int indexOf(final String value, final String needle, int offset, boolean caseSensitive) {
validate(value, NULL_STRING_PREDICATE, NULL_STRING_MSG_SUPPLIER);
if (caseSensitive) {
return value.indexOf(needle, offset);
}
return value.toLowerCase().indexOf(needle.toLowerCase(), offset);
}
/**
* Tests if two Strings are inequal
*
* @param first The first String
* @param second The second String
* @return true if first and second are not equal false otherwise
*/
public static boolean inequal(final String first, final String second) {
return !Objects.equals(first, second);
}
/**
* Inserts 'substr' into the 'value' at the 'index' provided.
*
* @param value The input String
* @param substr The String to insert
* @param index The index to insert substr
* @return String with substr added
*/
public static String insert(final String value, final String substr, final int index) {
validate(value, NULL_STRING_PREDICATE, NULL_STRING_MSG_SUPPLIER);
validate(substr, NULL_STRING_PREDICATE, NULL_STRING_MSG_SUPPLIER);
if (index > value.length()) {
return value;
}
return append(value.substring(0, index), substr, value.substring(index));
}
/**
* Verifies if String is uppercase
*
* @param value The input String
* @return true if String is uppercase false otherwise
*/
public static boolean isUpperCase(final String value) {
validate(value, NULL_STRING_PREDICATE, NULL_STRING_MSG_SUPPLIER);
return Objects.equals(value, value.toUpperCase());
}
/**
* Verifies if String is lower case
*
* @param value The input String
* @return true if String is lowercase false otherwise
*/
public static boolean isLowerCase(final String value) {
validate(value, NULL_STRING_PREDICATE, NULL_STRING_MSG_SUPPLIER);
return Objects.equals(value, value.toLowerCase());
}
/**
* Return the last n chars of String
*
* @param value The input String
* @param n Number of chars to return
* @return n Last characters
*/
public static String last(final String value, int n) {
validate(value, NULL_STRING_PREDICATE, NULL_STRING_MSG_SUPPLIER);
if (n > value.length()) {
return value;
}
return value.substring(value.length() - n);
}
/**
* Returns a new string of a given length such that the beginning of the string is padded.
*
* @param value The input String
* @param pad The pad
* @param length Length of the String we want
* @return Padded String
*/
public static String leftPad(final String value, final String pad, final int length) {
validate(value, NULL_STRING_PREDICATE, NULL_STRING_MSG_SUPPLIER);
validate(pad, NULL_STRING_PREDICATE, NULL_STRING_MSG_SUPPLIER);
if (value.length() > length) {
return value;
}
return append(repeat(pad, length - value.length()), value);
}
/**
* Checks whether Object is String
*
* @param value The input String
* @return true if Object is a String false otherwise
*/
public static boolean isString(final Object value) {
if (Objects.isNull(value)) {
throw new IllegalArgumentException("value can't be null");
}
return value instanceof String;
}
/**
* This method returns the index within the calling String object of the last occurrence of the specified value, searching backwards from the offset.
* Returns -1 if the value is not found. The search starts from the end and case sensitive.
*
* @param value The input String
* @param needle The search String
* @return Return position of the last occurrence of 'needle'.
*/
public static int lastIndexOf(final String value, final String needle) {
validate(value, NULL_STRING_PREDICATE, NULL_STRING_MSG_SUPPLIER);
return lastIndexOf(value, needle, value.length(), true);
}
/**
* This method returns the index within the calling String object of the last occurrence of the specified value, searching backwards from the offset.
* Returns -1 if the value is not found. The search starts from the end and case sensitive.
*
* @param value The input String
* @param needle The search String
* @return Return position of the last occurrence of 'needle'.
*/
public static int lastIndexOf(final String value, final String needle, boolean caseSensitive) {
validate(value, NULL_STRING_PREDICATE, NULL_STRING_MSG_SUPPLIER);
return lastIndexOf(value, needle, value.length(), caseSensitive);
}
/**
* This method returns the index within the calling String object of the last occurrence of the specified value, searching backwards from the offset.
* Returns -1 if the value is not found.
*
* @param value The input String
* @param needle The search String
* @param offset The index to start search from
* @param caseSensitive whether search should be case sensitive
* @return Return position of the last occurrence of 'needle'.
*/
public static int lastIndexOf(final String value, final String needle, final int offset, final boolean caseSensitive) {
validate(value, NULL_STRING_PREDICATE, NULL_STRING_MSG_SUPPLIER);
validate(needle, NULL_STRING_PREDICATE, NULL_STRING_MSG_SUPPLIER);
if (caseSensitive) {
return value.lastIndexOf(needle, offset);
}
return value.toLowerCase().lastIndexOf(needle.toLowerCase(), offset);
}
/**
* Removes all spaces on left
*
* @param value The input String
* @return String without left border spaces
*/
public static String leftTrim(final String value) {
validate(value, NULL_STRING_PREDICATE, NULL_STRING_MSG_SUPPLIER);
return value.replaceAll("^\\s+", "");
}
/**
* Returns length of String. Delegates to java.lang.String length method.
*
* @param value The input String
* @return Length of the String
*/
public static int length(final String value) {
validate(value, NULL_STRING_PREDICATE, NULL_STRING_MSG_SUPPLIER);
return value.length();
}
/**
* Return a new String starting with prepends
*
* @param value The input String
* @param prepends Strings to prepend
* @return The prepended String
*/
public static String prepend(final String value, final String... prepends) {
return prependArray(value, prepends);
}
/**
* Return a new String starting with prepends
*
* @param value The input String
* @param prepends Strings to prepend
* @return The prepended String
*/
public static String prependArray(final String value, final String[] prepends) {
validate(value, NULL_STRING_PREDICATE, NULL_STRING_MSG_SUPPLIER);
if (prepends == null || prepends.length == 0) {
return value;
}
StringJoiner joiner = new StringJoiner("");
for (String prepend : prepends) {
joiner.add(prepend);
}
return joiner.toString() + value;
}
/**
* Remove empty Strings from string array
*
* @param strings Array of String to be cleaned
* @return Array of String without empty Strings
*/
public static String[] removeEmptyStrings(String[] strings) {
if (Objects.isNull(strings)) {
throw new IllegalArgumentException("Input array should not be null");
}
return Arrays.stream(strings).filter(str -> str != null && !str.trim().isEmpty()).toArray(String[]::new);
}
/**
* Returns a new String with the prefix removed, if present. This is case sensitive.
*
* @param value The input String
* @param prefix String to remove on left
* @return The String without prefix
*/
public static String removeLeft(final String value, final String prefix) {
return removeLeft(value, prefix, true);
}
/**
* Returns a new String with the prefix removed, if present.
*
* @param value The input String
* @param prefix String to remove on left
* @param caseSensitive ensure case sensitivity
* @return The String without prefix
*/
public static String removeLeft(final String value, final String prefix, final boolean caseSensitive) {
validate(value, NULL_STRING_PREDICATE, NULL_STRING_MSG_SUPPLIER);
validate(prefix, NULL_STRING_PREDICATE, NULL_STRING_MSG_SUPPLIER);
BiFunction<String, String, String> fx = (f, s) -> f.startsWith(s) ? f.replaceFirst(s, "") : f;
if (caseSensitive) {
return fx.apply(value, prefix);
}
return fx.apply(value.toLowerCase(), prefix.toLowerCase());
}
/**
* Remove all non word characters.
*
* @param value The input String
* @return String without non-word characters
*/
public static String removeNonWords(final String value) {
validate(value, NULL_STRING_PREDICATE, NULL_STRING_MSG_SUPPLIER);
return value.replaceAll("[^\\w]+", "");
}
/**
* Returns a new string with the 'suffix' removed, if present. Search is case sensitive.
*
* @param value The input String
* @param suffix The suffix to remove
* @return The String without suffix!
*/
public static String removeRight(final String value, final String suffix) {
return removeRight(value, suffix, true);
}
/**
* Returns a new string with the 'suffix' removed, if present.
*
* @param value The input String
* @param suffix The suffix to remove
* @param caseSensitive whether search should be case sensitive or not
* @return The String without suffix!
*/
public static String removeRight(final String value, final String suffix, final boolean caseSensitive) {
validate(value, NULL_STRING_PREDICATE, NULL_STRING_MSG_SUPPLIER);
validate(suffix, NULL_STRING_PREDICATE, NULL_STRING_MSG_SUPPLIER);
return endsWith(value, suffix, caseSensitive) ? value.substring(0, value.toLowerCase().lastIndexOf(suffix.toLowerCase())) : value;
}
/**
* Remove all spaces and replace for value.
*
* @param value The input String
* @return String without spaces
*/
public static String removeSpaces(final String value) {
validate(value, NULL_STRING_PREDICATE, NULL_STRING_MSG_SUPPLIER);
return value.replaceAll("\\s", "");
}
/**
* Returns a repeated string given a multiplier.
*
* @param value The input String
* @param multiplier Number of repeats
* @return The String repeated
*/
public static String repeat(final String value, final int multiplier) {
validate(value, NULL_STRING_PREDICATE, NULL_STRING_MSG_SUPPLIER);
return Stream.generate(() -> value).limit(multiplier).collect(joining());
}
/**
* Replace all occurrences of 'search' value to 'newvalue'. Uses String replace method.
*
* @param value The input
* @param search The String to search
* @param newValue The String to replace
* @param caseSensitive whether search should be case sensitive or not
* @return String replaced with 'newvalue'.
*/
public static String replace(final String value, final String search, final String newValue, final boolean caseSensitive) {
validate(value, NULL_STRING_PREDICATE, NULL_STRING_MSG_SUPPLIER);
validate(search, NULL_STRING_PREDICATE, NULL_STRING_MSG_SUPPLIER);
if (caseSensitive) {
return value.replace(search, newValue);
}
return value.toLowerCase().replace(search.toLowerCase(), newValue);
}
/**
* Reverse the input String
*
* @param value The input String
* @return Reversed String
*/
public static String reverse(final String value) {
validate(value, NULL_STRING_PREDICATE, NULL_STRING_MSG_SUPPLIER);
return new StringBuilder(value).reverse().toString();
}
/**
* Returns a new string of a given length such that the ending of the string is padded.
*
* @param value The input String
* @param length Max length of String.
* @param pad Character to repeat
* @return Right padded String
*/
public static String rightPad(final String value, String pad, final int length) {
validate(value, NULL_STRING_PREDICATE, NULL_STRING_MSG_SUPPLIER);
if (value.length() > length) {
return value;
}
return append(value, repeat(pad, length - value.length()));
}
/**
* Remove all spaces on right.
*
* @param value The String
* @return String without right boarders spaces.
*/
public static String rightTrim(final String value) {
validate(value, NULL_STRING_PREDICATE, NULL_STRING_MSG_SUPPLIER);
return value.replaceAll("\\s+$", "");
}
/**
* Truncate the string securely, not cutting a word in half. It always returns the last full word.
*
* @param value The input String
* @param length Max size of the truncated String
* @param filler String that will be added to the end of the return string. Example: '...'
* @return The truncated String
*/
public static String safeTruncate(final String value, final int length, final String filler) {
validate(value, NULL_STRING_PREDICATE, NULL_STRING_MSG_SUPPLIER);
if (length == 0) {
return "";
}
if (length >= value.length()) {
return value;
}
String[] words = words(value);
StringJoiner result = new StringJoiner(" ");
int spaceCount = 0;
for (String word : words) {
if (result.length() + word.length() + filler.length() + spaceCount > length) {
break;
} else {
result.add(word);
spaceCount++;
}
}
return append(result.toString(), filler);
}
/**
* Alias to String split function. Defined only for completeness.
*
* @param value The input String
* @param regex The delimiting regular expression
* @return String Array
*/
public static String[] split(final String value, final String regex) {
validate(value, NULL_STRING_PREDICATE, NULL_STRING_MSG_SUPPLIER);
return value.split(regex);
}
/**
* Splits a String to words
*
* @param value The input String
* @return Words Array
*/
public static String[] words(final String value) {
validate(value, NULL_STRING_PREDICATE, NULL_STRING_MSG_SUPPLIER);
return value.split("\\W+");
}
/**
* Truncate the unsecured form string, cutting the independent string of required position.
*
* @param value Value will be truncated unsecurely.
* @param length Size of the returned string.
* @param filler Value that will be added to the end of the return string. Example: '...'
* @return String truncated unsafely.
*/
public static String truncate(final String value, final int length, final String filler) {
validate(value, NULL_STRING_PREDICATE, NULL_STRING_MSG_SUPPLIER);
if (length == 0) {
return "";
}
if (length >= value.length()) {
return value;
}
return append(value.substring(0, length - filler.length()), filler);
}
public static String decode(final String value, final int digits, final int radix) {
validate(value, NULL_STRING_PREDICATE, NULL_STRING_MSG_SUPPLIER);
return Arrays
.stream(value.split("(?<=\\G.{" + digits + "})"))
.map(data -> String.valueOf(Character.toChars(Integer.parseInt(data, radix))))
.collect(joining());
}
public static String encode(final String value, final int digits, final int radix) {
validate(value, NULL_STRING_PREDICATE, NULL_STRING_MSG_SUPPLIER);
return value.chars().mapToObj(ch -> leftPad(Integer.toString(ch, radix), "0", digits)).collect(joining());
}
private static void validate(String value, Predicate<String> predicate, final Supplier<String> supplier) {
if (predicate.test(value)) {
throw new IllegalArgumentException(supplier.get());
}
}
private static long countSubstr(String value, String subStr, boolean allowOverlapping, long count) {
int position = value.indexOf(subStr);
if (position == -1) {
return count;
}
int offset;
if (!allowOverlapping) {
offset = position + subStr.length();
} else {
offset = position + 1;
}
return countSubstr(value.substring(offset), subStr, allowOverlapping, ++count);
}
}