Extension.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.catalina.util;
import java.util.StringTokenizer;
/**
* Utility class that represents either an available "Optional Package" (formerly known as "Standard Extension") as
* described in the manifest of a JAR file, or the requirement for such an optional package. It is used to support the
* requirements of the Servlet Specification, version 2.3, related to providing shared extensions to all webapps.
* <p>
* In addition, static utility methods are available to scan a manifest and return an array of either available or
* required optional modules documented in that manifest.
* <p>
* For more information about optional packages, see the document <em>Optional Package Versioning</em> in the
* documentation bundle for your Java2 Standard Edition package, in file <code>guide/extensions/versioning.html</code>.
*
* @author Craig McClanahan
* @author Justyna Horwat
* @author Greg Murray
*/
public final class Extension {
// ------------------------------------------------------------- Properties
/**
* The name of the optional package being made available, or required.
*/
private String extensionName = null;
public String getExtensionName() {
return this.extensionName;
}
public void setExtensionName(String extensionName) {
this.extensionName = extensionName;
}
/**
* The URL from which the most recent version of this optional package can be obtained if it is not already
* installed.
*/
private String implementationURL = null;
public String getImplementationURL() {
return this.implementationURL;
}
public void setImplementationURL(String implementationURL) {
this.implementationURL = implementationURL;
}
/**
* The name of the company or organization that produced this implementation of this optional package.
*/
private String implementationVendor = null;
public String getImplementationVendor() {
return this.implementationVendor;
}
public void setImplementationVendor(String implementationVendor) {
this.implementationVendor = implementationVendor;
}
/**
* The unique identifier of the company that produced the optional package contained in this JAR file.
*/
private String implementationVendorId = null;
public String getImplementationVendorId() {
return this.implementationVendorId;
}
public void setImplementationVendorId(String implementationVendorId) {
this.implementationVendorId = implementationVendorId;
}
/**
* The version number (dotted decimal notation) for this implementation of the optional package.
*/
private String implementationVersion = null;
public String getImplementationVersion() {
return this.implementationVersion;
}
public void setImplementationVersion(String implementationVersion) {
this.implementationVersion = implementationVersion;
}
/**
* The name of the company or organization that originated the specification to which this optional package
* conforms.
*/
private String specificationVendor = null;
public String getSpecificationVendor() {
return this.specificationVendor;
}
public void setSpecificationVendor(String specificationVendor) {
this.specificationVendor = specificationVendor;
}
/**
* The version number (dotted decimal notation) of the specification to which this optional package conforms.
*/
private String specificationVersion = null;
public String getSpecificationVersion() {
return this.specificationVersion;
}
public void setSpecificationVersion(String specificationVersion) {
this.specificationVersion = specificationVersion;
}
/**
* fulfilled is true if all the required extension dependencies have been satisfied
*/
private boolean fulfilled = false;
public void setFulfilled(boolean fulfilled) {
this.fulfilled = fulfilled;
}
public boolean isFulfilled() {
return fulfilled;
}
// --------------------------------------------------------- Public Methods
/**
* Return <code>true</code> if the specified <code>Extension</code> (which represents an optional package required
* by this application) is satisfied by this <code>Extension</code> (which represents an optional package that is
* already installed. Otherwise, return <code>false</code>.
*
* @param required Extension of the required optional package
*
* @return <code>true</code> if the extension is satisfied
*/
public boolean isCompatibleWith(Extension required) {
// Extension Name must match
if (extensionName == null) {
return false;
}
if (!extensionName.equals(required.getExtensionName())) {
return false;
}
// If specified, available specification version must be >= required
if (required.getSpecificationVersion() != null) {
if (!isNewer(specificationVersion, required.getSpecificationVersion())) {
return false;
}
}
// If specified, Implementation Vendor ID must match
if (required.getImplementationVendorId() != null) {
if (implementationVendorId == null) {
return false;
}
if (!implementationVendorId.equals(required.getImplementationVendorId())) {
return false;
}
}
// If specified, Implementation version must be >= required
if (required.getImplementationVersion() != null) {
if (!isNewer(implementationVersion, required.getImplementationVersion())) {
return false;
}
}
// This available optional package satisfies the requirements
return true;
}
@Override
public String toString() {
StringBuilder sb = new StringBuilder("Extension[");
sb.append(extensionName);
if (implementationURL != null) {
sb.append(", implementationURL=");
sb.append(implementationURL);
}
if (implementationVendor != null) {
sb.append(", implementationVendor=");
sb.append(implementationVendor);
}
if (implementationVendorId != null) {
sb.append(", implementationVendorId=");
sb.append(implementationVendorId);
}
if (implementationVersion != null) {
sb.append(", implementationVersion=");
sb.append(implementationVersion);
}
if (specificationVendor != null) {
sb.append(", specificationVendor=");
sb.append(specificationVendor);
}
if (specificationVersion != null) {
sb.append(", specificationVersion=");
sb.append(specificationVersion);
}
sb.append(']');
return sb.toString();
}
// -------------------------------------------------------- Private Methods
/**
* Return <code>true</code> if the first version number is greater than or equal to the second; otherwise return
* <code>false</code>.
*
* @param first First version number (dotted decimal)
* @param second Second version number (dotted decimal)
*
* @exception NumberFormatException on a malformed version number
*/
private boolean isNewer(String first, String second) throws NumberFormatException {
if ((first == null) || (second == null)) {
return false;
}
if (first.equals(second)) {
return true;
}
StringTokenizer fTok = new StringTokenizer(first, ".", true);
StringTokenizer sTok = new StringTokenizer(second, ".", true);
int fVersion = 0;
int sVersion = 0;
while (fTok.hasMoreTokens() || sTok.hasMoreTokens()) {
if (fTok.hasMoreTokens()) {
fVersion = Integer.parseInt(fTok.nextToken());
} else {
fVersion = 0;
}
if (sTok.hasMoreTokens()) {
sVersion = Integer.parseInt(sTok.nextToken());
} else {
sVersion = 0;
}
if (fVersion < sVersion) {
return false;
} else if (fVersion > sVersion) {
return true;
}
if (fTok.hasMoreTokens()) {
fTok.nextToken();
}
if (sTok.hasMoreTokens()) {
sTok.nextToken();
}
}
return true; // Exact match
}
}