de.larssh.utils.text.StringConverters Maven / Gradle / Ivy
// Generated by delombok at Sat Apr 03 10:50:23 UTC 2021
package de.larssh.utils.text;
import java.io.UncheckedIOException;
import java.io.UnsupportedEncodingException;
import java.net.URLDecoder;
import java.net.URLEncoder;
import java.nio.charset.StandardCharsets;
import java.util.Base64;
import edu.umd.cs.findbugs.annotations.SuppressFBWarnings;
/**
* This class contains helper methods for decoding and encoding strings.
*/
public final class StringConverters {
/**
* Decodes {@code value} as Base64 string.
*
*
* This method is equivalent to using {@link Base64#getDecoder()} with the char
* set {@link Strings#DEFAULT_CHARSET}.
*
* @param value the value to be decoded
* @return the decoded value
*/
public static String decodeBase64(final String value) {
return new String(Base64.getDecoder().decode(value), Strings.DEFAULT_CHARSET);
}
/**
* Decodes {@code value} using the Base64 MIME type decoding scheme.
*
*
* This method is equivalent to using {@link Base64#getMimeDecoder()} with the
* char set {@link Strings#DEFAULT_CHARSET}.
*
* @param value the value to be decoded
* @return the decoded value
*/
public static String decodeBase64Mime(final String value) {
return new String(Base64.getMimeDecoder().decode(value), Strings.DEFAULT_CHARSET);
}
/**
* Decodes {@code value} as Base64 URL and filename-safe string.
*
*
* This method is equivalent to using {@link Base64#getUrlDecoder()} with the
* char set {@link Strings#DEFAULT_CHARSET}.
*
* @param value the value to be decoded
* @return the decoded value
*/
public static String decodeBase64Url(final String value) {
return new String(Base64.getUrlDecoder().decode(value), Strings.DEFAULT_CHARSET);
}
/**
* Decodes {@code value} as single CSV value if {@code value} starts with
* {@code escaper}. Otherwise {@code value} is returned as-is.
*
*
* Examples:
*
* Examples
*
* Parameter
* Return Value
*
*
* EMPTY
* EMPTY
*
*
* abc
* abc
*
*
* ""
* EMPTY
*
*
* "abc"
* abc
*
*
* "abc""xyz"
* abc"xyz
*
*
* """"
* "
*
*
*
* @param value the value to be decoded
* @param escaper the escaping character
* @return the decoded value
* @throws ParseException if the CSV value ends unexpectedly or some occurrence
* of {@code escaper} is not escaped correctly
*/
@SuppressWarnings("PMD.CyclomaticComplexity")
public static String decodeCsv(final String value, final char escaper) throws ParseException {
if (value.isEmpty() || value.charAt(0) != escaper) {
return value;
}
final int length = value.length();
if (length < 2) {
throw new ParseException("Value starts with the escape character. Expected a matching trailing character, but found none.");
}
if (value.charAt(length - 1) != escaper) {
throw new ParseException("Value starts with the escape character. Expected a matching trailing character, but found [%s].", value.charAt(length - 1));
}
int index = 1;
final StringBuilder builder = new StringBuilder(length - 2);
while (index < length - 1) {
final char character = value.charAt(index);
if (character == escaper) {
index += 1;
if (index >= length - 1) {
throw new ParseException("Unexpected end after escape character in [%s].", value);
}
if (value.charAt(index) != escaper) {
throw new ParseException("Unexpected character \"%s\" at index %d after escape character.", value.charAt(index), index);
}
}
builder.append(character);
index += 1;
}
return builder.length() == length ? value : builder.toString();
}
/**
* Decodes an {@code application/x-www-form-urlencoded} string.
*
*
* This method is equivalent to using {@link URLDecoder#decode(String)} with the
* char set {@link StandardCharsets#UTF_8} as the
*
* World Wide Web Consortium Recommendation states that UTF-8 should be
* used.
*
* @param value the value to be decoded
* @return the decoded value
* @throws ParseException on illegal or incomplete hex characters
*/
@SuppressFBWarnings(value = "EXS_EXCEPTION_SOFTENING_NO_CONSTRAINTS", justification = "converting checked to unchecked exception, that should never be thrown at all")
public static String decodeUrl(final String value) throws ParseException {
try {
return URLDecoder.decode(value, StandardCharsets.UTF_8.name());
} catch (final IllegalArgumentException e) {
throw new ParseException(e, "Failed decoding URL.");
} catch (final UnsupportedEncodingException e) {
throw new UncheckedIOException(e);
}
}
/**
* Translates {@code value} into Base64 format.
*
*
* This method is equivalent to using {@link Base64#getEncoder()} with the char
* set {@link Strings#DEFAULT_CHARSET}.
*
* @param value the value to be encoded
* @return the encoded value
*/
public static String encodeBase64(final String value) {
return new String(Base64.getEncoder().encode(value.getBytes(Strings.DEFAULT_CHARSET)), Strings.DEFAULT_CHARSET);
}
/**
* Translates {@code value} into Base64 MIME type encoding scheme.
*
*
* This method is equivalent to using {@link Base64#getMimeEncoder()} with the
* char set {@link Strings#DEFAULT_CHARSET}.
*
* @param value the value to be encoded
* @return the encoded value
*/
public static String encodeBase64Mime(final String value) {
return new String(Base64.getMimeEncoder().encode(value.getBytes(Strings.DEFAULT_CHARSET)), Strings.DEFAULT_CHARSET);
}
/**
* Translates {@code value} into Base64 URL and filename-safe format.
*
*
* This method is equivalent to using {@link Base64#getUrlEncoder()} with the
* charset {@link Strings#DEFAULT_CHARSET}.
*
* @param value the value to be encoded
* @return the encoded value
*/
public static String encodeBase64Url(final String value) {
return new String(Base64.getUrlEncoder().encode(value.getBytes(Strings.DEFAULT_CHARSET)), Strings.DEFAULT_CHARSET);
}
/**
* Encodes {@code value} into a single CSV value. All occurrences of
* {@code escaper} are escaped (doubled). If {@code value} contains
* inappropriate characters, it is surrounded by {@code escaper}.
*
*
* Inappropriate characters are {@code '\r'}, {@code '\n'}, {@code escaper} and
* {@code separator}. The latter is used for the list of inappropriate
* characters only.
*
*
* Examples:
*
* Examples
*
* Parameter
* Return Value
*
*
* EMPTY
* EMPTY
*
*
* abc
* abc
*
*
* abc"xyz
* "abc""xyz"
*
*
* "
* """"
*
*
*
* @param value the value to be encoded
* @param escaper the escaping character
* @param separator the separator character
* @return the encoded value
*/
@SuppressWarnings("PMD.CyclomaticComplexity")
public static String encodeCsv(final String value, final char escaper, final char separator) {
if (escaper == separator) {
throw new IllegalArgumentException("Escape character and separator must not be equal.");
}
final int length = value.length();
final StringBuilder builder = new StringBuilder(length);
builder.append(escaper);
int beginIndex = 0;
boolean changed = false;
for (int index = 0; index < length; index += 1) {
final char character = value.charAt(index);
if (character == escaper) {
if (beginIndex < index) {
builder.append(value, beginIndex, index);
}
beginIndex = index + 1;
builder.append(escaper).append(escaper);
changed = true;
} else if (character == separator || character == '\r' || character == '\n') {
changed = true;
}
}
if (!changed) {
return value;
}
if (beginIndex < length) {
builder.append(value, beginIndex, length);
}
return builder.append(escaper).toString();
}
/**
* Translates a string into {@code application/x-www-form-urlencoded} format
* with the char set {@link StandardCharsets#UTF_8} as the
*
* World Wide Web Consortium Recommendation states that UTF-8 should be
* used.
*
* @param value the value to be encoded
* @return the encoded value
*/
@SuppressFBWarnings(value = "EXS_EXCEPTION_SOFTENING_NO_CONSTRAINTS", justification = "converting checked to unchecked exception, that should never be thrown at all")
public static String encodeUrl(final String value) {
try {
return URLEncoder.encode(value, StandardCharsets.UTF_8.name());
} catch (final UnsupportedEncodingException e) {
throw new UncheckedIOException(e);
}
}
@java.lang.SuppressWarnings("all")
@edu.umd.cs.findbugs.annotations.SuppressFBWarnings(justification = "generated code")
@lombok.Generated
private StringConverters() {
throw new java.lang.UnsupportedOperationException("This is a utility class and cannot be instantiated");
}
}