| /* java.lang.Package - Everything you ever wanted to know about a package. |
| Copyright (C) 2000, 2001 Free Software Foundation, Inc. |
| |
| This file is part of GNU Classpath. |
| |
| GNU Classpath is free software; you can redistribute it and/or modify |
| it under the terms of the GNU General Public License as published by |
| the Free Software Foundation; either version 2, or (at your option) |
| any later version. |
| |
| GNU Classpath is distributed in the hope that it will be useful, but |
| WITHOUT ANY WARRANTY; without even the implied warranty of |
| MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| General Public License for more details. |
| |
| You should have received a copy of the GNU General Public License |
| along with GNU Classpath; see the file COPYING. If not, write to the |
| Free Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA |
| 02111-1307 USA. |
| |
| Linking this library statically or dynamically with other modules is |
| making a combined work based on this library. Thus, the terms and |
| conditions of the GNU General Public License cover the whole |
| combination. |
| |
| As a special exception, the copyright holders of this library give you |
| permission to link this library with independent modules to produce an |
| executable, regardless of the license terms of these independent |
| modules, and to copy and distribute the resulting executable under |
| terms of your choice, provided that you also meet, for each linked |
| independent module, the terms and conditions of the license of that |
| module. An independent module is a module which is not derived from |
| or based on this library. If you modify this library, you may extend |
| this exception to your version of the library, but you are not |
| obligated to do so. If you do not wish to do so, delete this |
| exception statement from your version. */ |
| |
| package java.lang; |
| |
| import java.net.URL; |
| import java.util.NoSuchElementException; |
| import java.util.StringTokenizer; |
| |
| /** |
| * Everything you ever wanted to know about a package. This class makes it |
| * possible to attach specification and implementation information to a |
| * package as explained in the |
| * <a href="http://java.sun.com/products/jdk/1.3/docs/guide/versioning/spec/VersioningSpecification.html#PackageVersionSpecification">Package Versioning Specification</a> |
| * section of the |
| * <a href="http://java.sun.com/products/jdk/1.3/docs/guide/versioning/spec/VersioningSpecification.html">Product Versioning Specification</a>. |
| * It also allows packages to be sealed with respect to the originating URL. |
| * <p> |
| * The most useful method is the <code>isCompatibleWith()</code> method that |
| * compares a desired version of a specification with the version of the |
| * specification as implemented by a package. A package is considered |
| * compatible with another version if the version of the specification is |
| * equal or higher then the requested version. Version numbers are represented |
| * as strings of positive numbers separated by dots (e.g. "1.2.0"). |
| * The first number is called the major number, the second the minor, |
| * the third the micro, etc. A version is considered higher then another |
| * version if it has a bigger major number then the another version or when |
| * the major numbers of the versions are equal if it has a bigger minor number |
| * then the other version, etc. (If a version has no minor, micro, etc numbers |
| * then they are considered the be 0.) |
| * |
| * @since 1.2 |
| * @author Mark Wielaard (mark@klomp.org) |
| */ |
| public class Package |
| { |
| /** The name of the Package */ |
| final private String name; |
| |
| /** The name if the implementation */ |
| final private String implTitle; |
| /** The vendor that wrote this implementation */ |
| final private String implVendor; |
| /** The version of this implementation */ |
| final private String implVersion; |
| |
| /** The name of the specification */ |
| final private String specTitle; |
| /** The name of the specification designer */ |
| final private String specVendor; |
| /** The version of this specification */ |
| final private String specVersion; |
| |
| /** If sealed the origin of the package classes, otherwise null */ |
| final private URL sealed; |
| |
| /** |
| * A package local constructor for the Package class. |
| * All parameters except the <code>name</code> of the package may be |
| * <code>null</code>. |
| * There are no public constructors defined for Package this is a package |
| * local constructor that is used by java.lang.Classloader.definePackage(). |
| * |
| * @param name The name of the Package |
| * @param specTitle The name of the specification |
| * @param specVendor The name of the specification designer |
| * @param specVersion The version of this specification |
| * @param implTitle The name of the implementation |
| * @param implVendor The vendor that wrote this implementation |
| * @param implVersion The version of this implementation |
| * @param sealed If sealed the origin of the package classes |
| */ |
| Package(String name, |
| String specTitle, String specVendor, String specVersion, |
| String implTitle, String implVendor, String implVersion, URL sealed) |
| { |
| if (name == null) |
| throw new IllegalArgumentException("null Package name"); |
| |
| this.name = name; |
| |
| this.implTitle = implTitle; |
| this.implVendor = implVendor; |
| this.implVersion = implVersion; |
| |
| this.specTitle = specTitle; |
| this.specVendor = specVendor; |
| this.specVersion = specVersion; |
| |
| this.sealed = sealed; |
| } |
| |
| /** |
| * Returns the Package name. |
| */ |
| public String getName() |
| { |
| return name; |
| } |
| |
| /** |
| * Returns the name of the implementation or null if unknown. |
| */ |
| public String getImplementationTitle() |
| { |
| return implTitle; |
| } |
| |
| /** |
| * Returns the vendor that wrote this implementation or null if unknown. |
| */ |
| public String getImplementationVendor() |
| { |
| return implVendor; |
| } |
| |
| /** |
| * Returns the version of this implementation or null if unknown. |
| */ |
| public String getImplementationVersion() |
| { |
| return implVersion; |
| } |
| |
| /** |
| * Returns the name of the specification or null if unknown. |
| */ |
| public String getSpecificationTitle() |
| { |
| return specTitle; |
| } |
| |
| /** |
| * Returns the name of the specification designer or null if unknown. |
| */ |
| public String getSpecificationVendor() |
| { |
| return specVendor; |
| } |
| |
| /** |
| * Returns the version of the specification or null if unknown. |
| */ |
| public String getSpecificationVersion() |
| { |
| return specVersion; |
| } |
| |
| /** |
| * Returns true if this Package is sealed. |
| */ |
| public boolean isSealed() |
| { |
| return (sealed != null); |
| } |
| |
| /** |
| * Returns true if this Package is sealed and the origin of the classes is |
| * the given URL. |
| * |
| * @param url |
| */ |
| public boolean isSealed(URL url) |
| { |
| return url.equals(sealed); |
| } |
| |
| /** |
| * Checks if the version of the specification is higher or at least as high |
| * as the desired version. |
| * @param version the (minimal) desired version of the specification |
| * @exception NumberFormatException when either version or the |
| * specification version is not a correctly formatted version number |
| * @exception NullPointerException if the supplied version or the |
| * Package specification version is null. |
| */ |
| public boolean isCompatibleWith(String version) throws NumberFormatException |
| { |
| StringTokenizer versionTokens = new StringTokenizer(version, "."); |
| StringTokenizer specTokens = new StringTokenizer(specVersion, "."); |
| try |
| { |
| while (versionTokens.hasMoreElements()) |
| { |
| int vers = Integer.parseInt(versionTokens.nextToken()); |
| int spec = Integer.parseInt(specTokens.nextToken()); |
| if (spec < vers) |
| return false; |
| else if (spec > vers) |
| return true; |
| // They must be equal, next Token please! |
| } |
| } |
| catch (NoSuchElementException e) |
| { |
| // this must have been thrown by spec.netToken() so return false |
| return false; |
| } |
| |
| // They must have been exactly the same version. |
| // Or the specVersion has more subversions. That is also good. |
| return true; |
| } |
| |
| /** |
| * Returns the named package if it is known by the callers class loader. |
| * It may return null if the package is unknown, when there is no |
| * information on that particular package available or when the callers |
| * classloader is null. |
| * @param name the name of the desired package |
| */ |
| public static Package getPackage(String name) |
| { |
| // Get the caller's classloader |
| SecurityManager sm = System.getSecurityManager(); |
| Class c = sm.getClassContext()[1]; |
| ClassLoader cl = c.getClassLoader(); |
| |
| if (cl != null) |
| return cl.getPackage(name); |
| else |
| return null; |
| } |
| |
| /** |
| * Returns all the packages that are known to the callers class loader. |
| * It may return an empty array if the classloader of the caller is null. |
| */ |
| public static Package[] getPackages() |
| { |
| // Get the caller's classloader |
| SecurityManager sm = System.getSecurityManager(); |
| Class c = sm.getClassContext()[1]; |
| ClassLoader cl = c.getClassLoader(); |
| |
| if (cl != null) |
| return cl.getPackages(); |
| else |
| return new Package[0]; |
| } |
| |
| /** |
| * Returns the hashCode of the name of this package. |
| */ |
| public int hashCode() |
| { |
| return name.hashCode(); |
| } |
| |
| /** |
| * Returns a string representation of this package name, specification, |
| * implementation and class origin if sealed. |
| */ |
| public String toString() |
| { |
| return "package: " + name + |
| " spec: " + specTitle + |
| " version: " + specVersion + |
| " vendor: " + specVendor + |
| " implementation: " + implTitle + |
| " version: " + implVersion + |
| " vendor: " + implVendor + " sealed: " + sealed; |
| } |
| } |