ParameterParser.java
- /*
- * Licensed to the Apache Software Foundation (ASF) under one or more
- * contributor license agreements. See the NOTICE file distributed with
- * this work for additional information regarding copyright ownership.
- * The ASF licenses this file to You 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 org.apache.commons.fileupload2.core;
- import java.io.UnsupportedEncodingException;
- import java.util.HashMap;
- import java.util.Locale;
- import java.util.Map;
- /**
- * A simple parser intended to parse sequences of name/value pairs.
- * <p>
- * Parameter values are expected to be enclosed in quotes if they contain unsafe characters, such as '=' characters or separators. Parameter values are optional
- * and can be omitted.
- * </p>
- * <p>
- * {@code param1 = value; param2 = "anything goes; really"; param3}
- * </p>
- */
- public class ParameterParser {
- /**
- * String to be parsed.
- */
- private char[] chars;
- /**
- * Current position in the string.
- */
- private int pos;
- /**
- * Maximum position in the string.
- */
- private int len;
- /**
- * Start of a token.
- */
- private int i1;
- /**
- * End of a token.
- */
- private int i2;
- /**
- * Whether names stored in the map should be converted to lower case.
- */
- private boolean lowerCaseNames;
- /**
- * Default ParameterParser constructor.
- */
- public ParameterParser() {
- }
- /**
- * A helper method to process the parsed token. This method removes leading and trailing blanks as well as enclosing quotation marks, when necessary.
- *
- * @param quoted {@code true} if quotation marks are expected, {@code false} otherwise.
- * @return the token
- */
- private String getToken(final boolean quoted) {
- // Trim leading white spaces
- while (i1 < i2 && Character.isWhitespace(chars[i1])) {
- i1++;
- }
- // Trim trailing white spaces
- while (i2 > i1 && Character.isWhitespace(chars[i2 - 1])) {
- i2--;
- }
- // Strip away quotation marks if necessary
- if (quoted && i2 - i1 >= 2 && chars[i1] == '"' && chars[i2 - 1] == '"') {
- i1++;
- i2--;
- }
- String result = null;
- if (i2 > i1) {
- result = new String(chars, i1, i2 - i1);
- }
- return result;
- }
- /**
- * Tests if there any characters left to parse.
- *
- * @return {@code true} if there are unparsed characters, {@code false} otherwise.
- */
- private boolean hasChar() {
- return this.pos < this.len;
- }
- /**
- * Tests {@code true} if parameter names are to be converted to lower case when name/value pairs are parsed.
- *
- * @return {@code true} if parameter names are to be converted to lower case when name/value pairs are parsed. Otherwise returns {@code false}
- */
- public boolean isLowerCaseNames() {
- return this.lowerCaseNames;
- }
- /**
- * Tests if the given character is present in the array of characters.
- *
- * @param ch the character to test for presence in the array of characters
- * @param charray the array of characters to test against
- * @return {@code true} if the character is present in the array of characters, {@code false} otherwise.
- */
- private boolean isOneOf(final char ch, final char[] charray) {
- var result = false;
- for (final char element : charray) {
- if (ch == element) {
- result = true;
- break;
- }
- }
- return result;
- }
- /**
- * Parses a map of name/value pairs from the given array of characters. Names are expected to be unique.
- *
- * @param charArray the array of characters that contains a sequence of name/value pairs
- * @param separator the name/value pairs separator
- * @return a map of name/value pairs
- */
- public Map<String, String> parse(final char[] charArray, final char separator) {
- if (charArray == null) {
- return new HashMap<>();
- }
- return parse(charArray, 0, charArray.length, separator);
- }
- /**
- * Parses a map of name/value pairs from the given array of characters. Names are expected to be unique.
- *
- * @param charArray the array of characters that contains a sequence of name/value pairs
- * @param offset the initial offset.
- * @param length the length.
- * @param separator the name/value pairs separator
- * @return a map of name/value pairs
- */
- public Map<String, String> parse(final char[] charArray, final int offset, final int length, final char separator) {
- if (charArray == null) {
- return new HashMap<>();
- }
- final var params = new HashMap<String, String>();
- this.chars = charArray.clone();
- this.pos = offset;
- this.len = length;
- String paramName;
- String paramValue;
- while (hasChar()) {
- paramName = parseToken(new char[] { '=', separator });
- paramValue = null;
- if (hasChar() && charArray[pos] == '=') {
- pos++; // skip '='
- paramValue = parseQuotedToken(new char[] { separator });
- if (paramValue != null) {
- try {
- paramValue = RFC2231Utils.hasEncodedValue(paramName) ? RFC2231Utils.decodeText(paramValue) : MimeUtils.decodeText(paramValue);
- } catch (final UnsupportedEncodingException ignored) {
- // let's keep the original value in this case
- }
- }
- }
- if (hasChar() && charArray[pos] == separator) {
- pos++; // skip separator
- }
- if (paramName != null && !paramName.isEmpty()) {
- paramName = RFC2231Utils.stripDelimiter(paramName);
- if (this.lowerCaseNames) {
- paramName = paramName.toLowerCase(Locale.ROOT);
- }
- params.put(paramName, paramValue);
- }
- }
- return params;
- }
- /**
- * Parses a map of name/value pairs from the given string. Names are expected to be unique.
- *
- * @param str the string that contains a sequence of name/value pairs
- * @param separator the name/value pairs separator
- * @return a map of name/value pairs
- */
- public Map<String, String> parse(final String str, final char separator) {
- if (str == null) {
- return new HashMap<>();
- }
- return parse(str.toCharArray(), separator);
- }
- /**
- * Parses a map of name/value pairs from the given string. Names are expected to be unique. Multiple separators may be specified and the earliest found in
- * the input string is used.
- *
- * @param str the string that contains a sequence of name/value pairs
- * @param separators the name/value pairs separators
- * @return a map of name/value pairs
- */
- public Map<String, String> parse(final String str, final char[] separators) {
- if (separators == null || separators.length == 0) {
- return new HashMap<>();
- }
- var separator = separators[0];
- if (str != null) {
- var idx = str.length();
- for (final char separator2 : separators) {
- final var tmp = str.indexOf(separator2);
- if (tmp != -1 && tmp < idx) {
- idx = tmp;
- separator = separator2;
- }
- }
- }
- return parse(str, separator);
- }
- /**
- * Parses out a token until any of the given terminators is encountered outside the quotation marks.
- *
- * @param terminators the array of terminating characters. Any of these characters when encountered outside the quotation marks signify the end of the token
- * @return the token
- */
- private String parseQuotedToken(final char[] terminators) {
- char ch;
- i1 = pos;
- i2 = pos;
- var quoted = false;
- var charEscaped = false;
- while (hasChar()) {
- ch = chars[pos];
- if (!quoted && isOneOf(ch, terminators)) {
- break;
- }
- if (!charEscaped && ch == '"') {
- quoted = !quoted;
- }
- charEscaped = !charEscaped && ch == '\\';
- i2++;
- pos++;
- }
- return getToken(true);
- }
- /**
- * Parses out a token until any of the given terminators is encountered.
- *
- * @param terminators the array of terminating characters. Any of these characters when encountered signify the end of the token
- * @return the token
- */
- private String parseToken(final char[] terminators) {
- char ch;
- i1 = pos;
- i2 = pos;
- while (hasChar()) {
- ch = chars[pos];
- if (isOneOf(ch, terminators)) {
- break;
- }
- i2++;
- pos++;
- }
- return getToken(false);
- }
- /**
- * Sets the flag if parameter names are to be converted to lower case when name/value pairs are parsed.
- *
- * @param lowerCaseNames {@code true} if parameter names are to be converted to lower case when name/value pairs are parsed. {@code false} otherwise.
- */
- public void setLowerCaseNames(final boolean lowerCaseNames) {
- this.lowerCaseNames = lowerCaseNames;
- }
- }