/**
* Copyright 2005-2014 Restlet
*
* The contents of this file are subject to the terms of one of the following
* open source licenses: Apache 2.0 or or EPL 1.0 (the "Licenses"). You can
* select the license that you prefer but you may not use this file except in
* compliance with one of these Licenses.
*
* You can obtain a copy of the Apache 2.0 license at
* http://www.opensource.org/licenses/apache-2.0
*
* You can obtain a copy of the EPL 1.0 license at
* http://www.opensource.org/licenses/eclipse-1.0
*
* See the Licenses for the specific language governing permissions and
* limitations under the Licenses.
*
* Alternatively, you can obtain a royalty free commercial license with less
* limitations, transferable or non-transferable, directly at
* http://restlet.com/products/restlet-framework
*
* Restlet is a registered trademark of Restlet S.A.S.
*/
package org.restlet.ext.jaxrs.internal.util;
import java.lang.reflect.Method;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.regex.Matcher;
import java.util.regex.Pattern;
import javax.ws.rs.Path;
import org.restlet.engine.util.SystemUtils;
import org.restlet.ext.jaxrs.internal.exceptions.IllegalPathException;
import org.restlet.ext.jaxrs.internal.exceptions.IllegalPathOnClassException;
import org.restlet.ext.jaxrs.internal.exceptions.IllegalPathOnMethodException;
import org.restlet.ext.jaxrs.internal.exceptions.MissingAnnotationException;
/**
* Wraps a regular expression of a @{@link Path}. Instances are immutable.
* The regular expression has no '/' t the start.
*
* @author Stephan Koops
*/
public class PathRegExp {
/**
* Default regular expression to use, if no reg exp is given (matches every
* character expect '/').
*
* @see #defaultRegExp
*/
private static final String DEFAULT_REG_EXP = "[^/]+?";
/**
* The PathRegExp with an empty path.
*/
public static final PathRegExp EMPTY;
private static final byte NAME_READ = 2;
private static final byte NAME_READ_READY = 3;
private static final byte NAME_READ_START = 1;
private static final byte REGEXP_READ = 12;
private static final byte REGEXP_READ_READY = 13;
private static final byte REGEXP_READ_START = 11;
static {
try {
EMPTY = new PathRegExp("", null);
} catch (IllegalPathException e) {
throw new RuntimeException("This could not occur", e);
}
}
/**
* Creates a {@link PathRegExp} for a root resource class.
*
* @param rrc
* the JAX-RS root resource class
* @return the PathRegExp from the given root resource class
* @throws MissingAnnotationException
* if the {@link Path} annotation is missing.
* @throws IllegalPathOnClassException
* if the {@link Path} annotation is not valid.
* @throws IllegalArgumentException
* if the rrc is null.
* @see {@link #EMPTY}
*/
public static PathRegExp createForClass(Class<?> rrc)
throws MissingAnnotationException, IllegalPathOnClassException,
IllegalArgumentException {
final Path path = Util.getPathAnnotation(rrc);
try {
return new PathRegExp(path.value(), path);
} catch (IllegalPathException ipe) {
throw new IllegalPathOnClassException(ipe);
}
}
/**
* Creates a {@link PathRegExp} for a sub resource method or sub resource
* locator. Returns {@link #EMPTY}, if the method is not annotated with
* @Path.
*
* @param annotatedMethod
* @return the {@link PathRegExp}. Never returns null.
* @throws IllegalPathOnMethodException
* if the annotation on the method is invalid.
* @throws IllegalArgumentException
* if the method is null.
*/
public static PathRegExp createForMethod(Method annotatedMethod)
throws IllegalPathOnMethodException, IllegalArgumentException {
final Path pathAnno = Util.getPathAnnotationOrNull(annotatedMethod);
if (pathAnno == null) {
return EMPTY;
}
try {
return new PathRegExp(pathAnno.value(), pathAnno);
} catch (IllegalPathException ipe) {
throw new IllegalPathOnMethodException(ipe);
}
}
private final boolean emptyOrSlash;
/** Contains the number of literal chars in this Regular Expression */
private final Integer noLitChars;
/**
* Contains the number of capturing groups with regular expressions that are
* not the default.
*
* @see #DEFAULT_REG_EXP
*/
private int noNonDefaultRegExp = 0;
private final int noOfCapturingGroups;
private final String pathTemplateDec;
private final String pathTemplateEnc;
private final Pattern pattern;
private final List<String> varNames = new ArrayList<String>();
/**
* Is intended for internal use and testing. Otherwise use the static
* methods {@link #createForClass(Class)} or
* {@link #createForMethod(Method)}, or the constant {@link #EMPTY}.
*
* @param pathPattern
* @param pathForExcMess
*/
private PathRegExp(String pathTemplate, Path pathForExcMess)
throws IllegalPathException {
// 1. URI encode the template, ignoring URI template variable specs.
// 2. Escape any regular expression characters in the URI template,
// again ignoring URI template variable specifications.
// 3. Replace each URI template variable with a capturing group
// containing the specified regular expression or "([^/]+?)" if no
// regular expression is specified.
// LATER regexp in @Path: @Path("{p}/abc/{p}") is allowed, p may be != p
if (pathTemplate == null) {
throw new IllegalArgumentException(
"The path template must not be null");
}
final int l = pathTemplate.length();
final StringBuilder pathPattern = new StringBuilder();
int forStart = 0;
if (l > 0 && pathTemplate.charAt(0) == '/')
forStart = 1;
int noLitChars = 0;
int numberOfCapturingGroups = 0;
for (int i = forStart; i < l; i++) {
final char c = pathTemplate.charAt(i);
if (c == '{') {
i = processTemplVarname(pathTemplate, i, pathPattern,
pathForExcMess);
numberOfCapturingGroups++;
} else if (c == '%') {
try {
EncodeOrCheck.processPercent(i, true, pathTemplate,
pathPattern);
} catch (IllegalArgumentException e) {
throw new IllegalPathException(pathForExcMess, e);
}
} else if (c == '}') {
throw new IllegalPathException(pathForExcMess,
"'}' is only allowed as "
+ "end of a variable name in \"" + pathTemplate
+ "\"");
} else if (c == ';') {
throw new IllegalPathException(pathForExcMess,
"matrix parameters are not allowed in a @Path");
} else if (!false && (c == '/')) {
pathPattern.append(c);
noLitChars++;
} else {
noLitChars += EncodeOrCheck.encode(c, pathPattern);
}
}
this.noLitChars = noLitChars;
this.noOfCapturingGroups = numberOfCapturingGroups;
// 4. If the resulting string ends with "/" then remove the final char.
// 5. Append "(/.*)?" to the result.
if (pathPattern.length() > 0
&& pathPattern.charAt(pathPattern.length() - 1) != '/') {
pathPattern.append('/');
}
pathPattern.append("(.*)");
this.pattern = Pattern.compile(pathPattern.toString());
this.emptyOrSlash = Util.isEmptyOrSlash(pathTemplate);
if (l > 0) {
if (pathTemplate.charAt(0) != '/') {
pathTemplate = '/' + pathTemplate;
}
if (l > 1 && pathTemplate.endsWith("/")) {
pathTemplate = pathTemplate.substring(0,
pathTemplate.length() - 2);
}
}
this.pathTemplateEnc = pathTemplate; // LATER encode unencoded here
this.pathTemplateDec = pathTemplate; // LATER decode here
}
/**
* Compares this regular expression of a @{@link Path} with the given
* Object by comparing given patterns.
*/
@Override
public boolean equals(Object anotherObject) {
if (this == anotherObject) {
return true;
}
if (!(anotherObject instanceof PathRegExp)) {
return false;
}
final PathRegExp otherRegExp = (PathRegExp) anotherObject;
return this.pattern.pattern().equals(otherRegExp.pattern.pattern());
}
/**
* @return the number of capturing groups with regular expressions that are
* not the default.
*/
public int getNoNonDefCaprGroups() {
return this.noNonDefaultRegExp;
}
/**
* @return Returns the number of capturing groups.
*/
public int getNoOfCapturingGroups() {
return this.noOfCapturingGroups;
}
/**
* See Footnode to JSR-311-Spec, Section 2.6, Algorithm, Part 1e
*
* @return Returns the number of literal chars in the path patern
*/
public int getNoOfLiteralChars() {
return this.noLitChars;
}
/**
* @return the decoded path template with a '/' at the beginning, and no one
* at the end.
*/
public String getPathTemplateDec() {
return this.pathTemplateDec;
}
/**
* @return the encoded path template with a '/' at the beginning, and no one
* at the end.
*/
public String getPathTemplateEnc() {
return this.pathTemplateEnc;
}
@Override
public int hashCode() {
return SystemUtils.hashCode(this.pattern);
}
/**
* Checks if the URI template is empty or only a slash.
*
* @return if this path regular expression is empty or "/"
*/
public boolean isEmptyOrSlash() {
return this.emptyOrSlash;
}
/**
* Checks if this regular expression matches the given remaining path.
*
* @param remainingPath
* @return Returns an MatchingResult, if the remainingPath matches to this
* template, or null, if not.
*/
public MatchingResult match(RemainingPath remainingPath) {
String givenPath = remainingPath.getWithoutParams();
Matcher matcher = pattern.matcher(givenPath);
if (!matcher.matches()) {
return null;
}
final Map<String, String> templateVars = new HashMap<String, String>();
for (int i = 1; i < matcher.groupCount(); i++) {
templateVars.put(this.varNames.get(i - 1), matcher.group(i));
}
String finalCapturingGroup = matcher.group(matcher.groupCount());
// if (finalCapturingGroup.length() > 0) {
// if (pathSuppl && finalCapturingGroup.endsWith("/")) {
// finalCapturingGroup = finalCapturingGroup.substring(0,
// finalCapturingGroup.length() - 1);
// }
// if (!finalCapturingGroup.startsWith("/")) {
// finalCapturingGroup = "/" + finalCapturingGroup;
// }
// }
int matchedChars = givenPath.length() - finalCapturingGroup.length();
if ((matchedChars > 0) && (givenPath.charAt(matchedChars - 1) == '/')) {
matchedChars--; // ignore '/' at end
}
final String matchedPart = givenPath.substring(0, matchedChars);
return new MatchingResult(matchedPart, templateVars,
finalCapturingGroup);
}
/**
* Checks, if this regular expression matches the given path with no final
* matching group.
*
* @param remainingPath
* @return true, if this regular expression matches exectly the given path,
* without a final capturing group.
*/
public boolean matchesWithEmpty(RemainingPath remainingPath) {
final MatchingResult matchingResult = match(remainingPath);
if (matchingResult == null) {
return false;
}
return matchingResult.getFinalCapturingGroup().isEmptyOrSlash();
}
/**
* @param pathTemplate
* @param braceIndex
* @param pathPattern
* @param pathForExcMess
* @throws IllegalPathException
*/
private int processTemplVarname(final String pathTemplate,
final int braceIndex, final StringBuilder pathPattern,
final Path pathForExcMess) throws IllegalPathException {
pathPattern.append('(');
final int l = pathTemplate.length();
final StringBuilder varName = new StringBuilder();
final StringBuilder regExp = new StringBuilder();
int state = NAME_READ_START;
for (int i = braceIndex + 1; i < l; i++) {
final char c = pathTemplate.charAt(i);
if (c == '{') {
throw new IllegalPathException(pathForExcMess,
"A variable must not " + "contain an extra '{' in \""
+ pathTemplate + "\"");
} else if (c == ' ' || c == '\t') {
if (state == NAME_READ)
state = NAME_READ_READY;
else if (state == REGEXP_READ)
state = REGEXP_READ_READY;
continue;
} else if (c == ':') {
if (state == NAME_READ_START) {
throw new IllegalPathException(pathForExcMess,
"The variable name at position must not be null at "
+ braceIndex + " of \"" + pathTemplate
+ "\"");
}
if (state == NAME_READ || state == NAME_READ_READY) {
state = REGEXP_READ_START;
}
continue;
} else if (c == '}') {
if (state == NAME_READ_START) {
throw new IllegalPathException(pathForExcMess,
"The template variable name '{}' is not allowed in "
+ "\"" + pathTemplate + "\"");
} else if ((state == REGEXP_READ)
|| (state == REGEXP_READ_READY)) {
pathPattern.append(regExp);
if (!regExp.equals(DEFAULT_REG_EXP)) {
this.noNonDefaultRegExp++;
}
} else {
pathPattern.append(DEFAULT_REG_EXP);
}
pathPattern.append(')');
this.varNames.add(varName.toString());
return i;
}
if (state == NAME_READ_START) {
state = NAME_READ;
varName.append(c);
} else if (state == NAME_READ) {
varName.append(c);
} else if (state == REGEXP_READ_START) {
state = REGEXP_READ;
regExp.append(c);
} else if (state == REGEXP_READ) {
regExp.append(c);
} else {
throw new IllegalPathException(pathForExcMess,
"Invalid character found at position " + i + " of \""
+ pathTemplate + "\"");
}
}
throw new IllegalPathException(pathForExcMess,
"No '}' found after '{' " + "at position " + braceIndex
+ " of \"" + pathTemplate + "\"");
}
@Override
public String toString() {
return this.pattern.pattern();
}
}