policymetadata.java

来自「sunxacml源码」· Java 代码 · 共 344 行

/*
 * @(#)PolicyMetaData.java
 *
 * Copyright 2005-2006 Sun Microsystems, Inc. All Rights Reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *
 *   1. Redistribution of source code must retain the above copyright notice,
 *      this list of conditions and the following disclaimer.
 * 
 *   2. Redistribution in binary form must reproduce the above copyright
 *      notice, this list of conditions and the following disclaimer in the
 *      documentation and/or other materials provided with the distribution.
 *
 * Neither the name of Sun Microsystems, Inc. or the names of contributors may
 * be used to endorse or promote products derived from this software without
 * specific prior written permission.
 * 
 * This software is provided "AS IS," without a warranty of any kind. ALL
 * EXPRESS OR IMPLIED CONDITIONS, REPRESENTATIONS AND WARRANTIES, INCLUDING
 * ANY IMPLIED WARRANTY OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE
 * OR NON-INFRINGEMENT, ARE HEREBY EXCLUDED. SUN MICROSYSTEMS, INC. ("SUN")
 * AND ITS LICENSORS SHALL NOT BE LIABLE FOR ANY DAMAGES SUFFERED BY LICENSEE
 * AS A RESULT OF USING, MODIFYING OR DISTRIBUTING THIS SOFTWARE OR ITS
 * DERIVATIVES. IN NO EVENT WILL SUN OR ITS LICENSORS BE LIABLE FOR ANY LOST
 * REVENUE, PROFIT OR DATA, OR FOR DIRECT, INDIRECT, SPECIAL, CONSEQUENTIAL,
 * INCIDENTAL OR PUNITIVE DAMAGES, HOWEVER CAUSED AND REGARDLESS OF THE THEORY
 * OF LIABILITY, ARISING OUT OF THE USE OF OR INABILITY TO USE THIS SOFTWARE,
 * EVEN IF SUN HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES.
 *
 * You acknowledge that this software is not designed or intended for use in
 * the design, construction, operation or maintenance of any nuclear facility.
 */

package com.sun.xacml;

import com.sun.xacml.attr.AttributeFactory;
import com.sun.xacml.attr.AttributeFactoryProxy;

import com.sun.xacml.combine.CombiningAlgFactory;
import com.sun.xacml.combine.CombiningAlgFactoryProxy;

import com.sun.xacml.cond.FunctionFactory;
import com.sun.xacml.cond.FunctionFactoryProxy;


/**
 * This is used to share polcy meta-data throughout the policy tree. Examples
 * of common meta-data include the version of XACML or XPath being used in
 * a policy.
 *
 * @since 2.0
 * @author Seth Proctor
 */
public class PolicyMetaData
{

    /**
     * XACML 1.0 identifier
     */
    public static final String XACML_1_0_IDENTIFIER =
        "urn:oasis:names:tc:xacml:1.0:policy";

    /**
     * XACML 2.0 identifier
     */
    public static final String XACML_2_0_IDENTIFIER =
        "urn:oasis:names:tc:xacml:2.0:policy:schema:os";

    /**
     * Version identifier for XACML 1.0
     */
    public static final int XACML_VERSION_1_0 = 0;
    
    /**
     * Version identifier for XACML 1.1 (which isn't a formal release
     * so has no namespace string, but still exists as a separate
     * specification)
     */
    public static final int XACML_VERSION_1_1 = 1;

    /**
     * Version identifier for XACML 1.2
     */
    public static final int XACML_VERSION_2_0 = 2;

    /**
     * The default version of XACML, 1.0, used if no namespace string
     * is specified
     */
    public static final int XACML_DEFAULT_VERSION = XACML_VERSION_1_0;

    // private mapping from XACML version number to identifier string
    private static String [] xacmlIdentifiers = { XACML_1_0_IDENTIFIER,
                                                  XACML_1_0_IDENTIFIER,
                                                  XACML_2_0_IDENTIFIER };

    /**
     * XPath 1.0 identifier
     */
    public static final String XPATH_1_0_IDENTIFIER =
        "http://www.w3.org/TR/1999/Rec-xpath-19991116";

    /**
     * Version identifier for an unspecified version of XPath
     */
    public static final int XPATH_VERSION_UNSPECIFIED = 0;

    /**
     * Version identifier for XPath 1.0
     */
    public static final int XPATH_VERSION_1_0 = 1;

    // private mapping from XPath version number to identifier string
    private static String [] xpathIdentifiers = { null,
                                                  XPATH_1_0_IDENTIFIER };

    // the version of XACML
    private int xacmlVersion;

    // the version of XPath, or null if none is specified
    private int xpathVersion;

    // the factories used with this policy
    private AttributeFactoryProxy afProxy;
    private CombiningAlgFactoryProxy cafProxy;
    private FunctionFactoryProxy ffProxy;

    /**
     * Creates a <code>PolicyMetaData</code> instance with all the parameters
     * set to their default values.
     */
    public PolicyMetaData() {
        this(XACML_DEFAULT_VERSION, XPATH_VERSION_UNSPECIFIED);
    }

    /**
     * Creates a <code>PolicyMetaData</code> instance with the given
     * parameters. The default factories are assumed.
     *
     * @param xacmlVersion the version of XACML used in a policy
     * @param xpathVersion the XPath version to use in any selectors
     */
    public PolicyMetaData(int xacmlVersion, int xpathVersion) {
        this(xacmlVersion, xpathVersion, null, null, null);
    }

    /**
     * Creates a <code>PolicyMetaData</code> instance with the given
     * parameters. The default factories are assumed.
     *
     * @param xacmlVersion the version of XACML used in a policy
     * @param xpathVersion the XPath version to use in any selectors, or
     *                     null if this is unspecified (ie, not supplied in
     *                     the defaults section of the policy)
     *
     * @throws IllegalArgumentException if the identifier strings are unknown
     */
    public PolicyMetaData(String xacmlVersion, String xpathVersion) {
        this(xacmlVersion, xpathVersion, null, null, null);
    }

    /**
     * Creates a <code>PolicyMetaData</code> instance with the given
     * parameters. A proxy value of null implies the default factory.
     *
     * @param xacmlVersion the version of XACML used in a policy
     * @param xpathVersion the XPath version to use in any selectors
     * @param attributeFactoryProxy
     * @param combiningAlgFactoryProxy
     * @param functionFactoryProxy
     */
    public PolicyMetaData(int xacmlVersion, int xpathVersion,
                          AttributeFactoryProxy attributeFactoryProxy,
                          CombiningAlgFactoryProxy combiningAlgFactoryProxy,
                          FunctionFactoryProxy functionFactoryProxy) {
        this.xacmlVersion = xacmlVersion;
        this.xpathVersion = xpathVersion;

        proxySetup(attributeFactoryProxy, combiningAlgFactoryProxy,
                   functionFactoryProxy);
    }

    /**
     * Creates a <code>PolicyMetaData</code> instance with the given
     * parameters.
     *
     * @param xacmlVersion the version of XACML used in a policy
     * @param xpathVersion the XPath version to use in any selectors, or
     *                     null if this is unspecified (ie, not supplied in
     *                     the defaults section of the policy)
     * @param 
     *
     * @throws IllegalArgumentException if the identifier strings are unknown
     */
    public PolicyMetaData(String xacmlVersion, String xpathVersion,
                          AttributeFactoryProxy attributeFactoryProxy,
                          CombiningAlgFactoryProxy combiningAlgFactoryProxy,
                          FunctionFactoryProxy functionFactoryProxy) {
        if (xacmlVersion == null)
            this.xacmlVersion = XACML_DEFAULT_VERSION;
        else if (xacmlVersion.equals(XACML_1_0_IDENTIFIER))
            this.xacmlVersion = XACML_VERSION_1_0;
        else if (xacmlVersion.equals(XACML_2_0_IDENTIFIER))
            this.xacmlVersion = XACML_VERSION_2_0;
        else
            throw new IllegalArgumentException("Unknown XACML version " +
                                               "string: " + xacmlVersion);

        if (xpathVersion != null) {
            if (! xpathVersion.equals(XPATH_1_0_IDENTIFIER))
                throw new IllegalArgumentException("Unsupported XPath " +
                                                   " version: " +
                                                   xpathVersion);
            this.xpathVersion = XPATH_VERSION_1_0;
        } else {
            this.xpathVersion = XPATH_VERSION_UNSPECIFIED;
        }

        proxySetup(attributeFactoryProxy, combiningAlgFactoryProxy,
                   functionFactoryProxy);
    }

    /**
     *
     */
    private void proxySetup(AttributeFactoryProxy attributeFactoryProxy,
                            CombiningAlgFactoryProxy combiningAlgFactoryProxy,
                            FunctionFactoryProxy functionFactoryProxy) {
        if (attributeFactoryProxy == null)
            this.afProxy = new AttributeFactoryProxy() {
                    public AttributeFactory getFactory() {
                        return AttributeFactory.getInstance();
                    }
                };
        else
            this.afProxy = attributeFactoryProxy;

        if (combiningAlgFactoryProxy == null)
            this.cafProxy = new CombiningAlgFactoryProxy() {
                    public CombiningAlgFactory getFactory() {
                        return CombiningAlgFactory.getInstance();
                    }
                };
        else
            this.cafProxy = combiningAlgFactoryProxy;

        if (functionFactoryProxy == null)
            this.ffProxy = FunctionFactory.getInstance();
        else
            this.ffProxy = functionFactoryProxy;
    }

    /**
     * Returns which version of XACML is specified in this meta-data.
     *
     * @return the XACML version
     */
    public int getXACMLVersion() {
        return xacmlVersion;
    }

    /**
     * Returns the identifier string for the specified version of XACML.
     *
     * @return the identifier string
     */
    public String getXACMLIdentifier() {
        return xacmlIdentifiers[xacmlVersion];
    }

    /**
     * Returns which version of XPath is specified in this meta-data.
     *
     * @return the XPath version or null
     */
    public int getXPathVersion() {
        return xpathVersion;
    }

    /**
     * Returns the identifier string for the specified version of XPath, or
     * null if no version is specified.
     *
     * @return the identifier string or null
     */
    public String getXPathIdentifier() {
        return xpathIdentifiers[xpathVersion];
    }

    /**
     * Returns the <code>AttributeFactory</code> used by the associated
     * policy.
     *
     * @return a <code>AttributeFactory</code>
     */
    public AttributeFactory getAttributeFactory() {
        return afProxy.getFactory();
    }

    /**
     * Returns the <code>CombiningAlgFactory</code> used by the associated
     * policy.
     *
     * @return a <code>CombiningAlgFactory</code>
     */
    public CombiningAlgFactory getCombiningAlgFactory() {
        return cafProxy.getFactory();
    }

    /**
     * Returns the Target <code>FunctionFactory</code> used by the associated
     * policy.
     *
     * @return a <code>FunctionFactory</code>
     */
    public FunctionFactory getTargetFunctionFactory() {
        return ffProxy.getTargetFactory();
    }

    /**
     * Returns the Condition <code>FunctionFactory</code> used by the
     * associated policy.
     *
     * @return a <code>FunctionFactory</code>
     */
    public FunctionFactory getConditionFunctionFactory() {
        return ffProxy.getConditionFactory();
    }

    /**
     * Returns the General <code>FunctionFactory</code> used by the associated
     * policy.
     *
     * @return a <code>FunctionFactory</code>
     */
    public FunctionFactory getGeneralFunctionFactory() {
        return ffProxy.getGeneralFactory();
    }

}