JndiResourceCollectionFilter.java

/**
 * Copyright (c) 2009-2011 VMware, Inc. All Rights Reserved.
 *
 * Licensed 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 com.springsource.insight.plugin.jndi;

import java.util.Arrays;
import java.util.Collection;
import java.util.Collections;
import java.util.List;

import com.springsource.insight.collection.PatternedResourceCollectionFilter;
import com.springsource.insight.intercept.plugin.CollectionSettingName;
import com.springsource.insight.intercept.plugin.CollectionSettingsRegistry;
import com.springsource.insight.util.ArrayUtil;
import com.springsource.insight.util.ListUtil;
import com.springsource.insight.util.StringUtil;

/**
 *
 */
public class JndiResourceCollectionFilter extends PatternedResourceCollectionFilter {
    public static final CollectionSettingName INCLD_SETTING =
            new CollectionSettingName("included.resource.pattern", JndiPluginRuntimeDescriptor.PLUGIN_NAME, "Regexp used to select which names to intercept");
    public static final CollectionSettingName EXCLD_SETTING =
            new CollectionSettingName("excluded.resource.pattern", JndiPluginRuntimeDescriptor.PLUGIN_NAME, "Regexp used to select which names to ignore");
    /**
     * A {@link List} of <U>suffixes</U> automatically excluded. The main
     * reason for this list is the fact that Apache Tomcat uses JNDI to
     * look up classes as well as web rendering resources
     */
    public static final List<String> DEFAULT_EXCLUSION_PATTERNS =
            Collections.unmodifiableList(
                    Arrays.asList(".class", ".jpg", ".jpeg", ".gif", ".png", ".ico", ".bmp",
                            ".css", ".js", ".jsp", ".htm", ".html", ".asp", ".aspx",
                            ".xml", ".xsd", ".xslt", ".dtd", ".sql", ".jar", ".properties",
                            "MANIFEST.MF", "index.list"));

    private static final JndiResourceCollectionFilter FILTER = new JndiResourceCollectionFilter();

    private JndiResourceCollectionFilter() {
        this(CollectionSettingsRegistry.getInstance());
    }

    public static final JndiResourceCollectionFilter getIntance() {
        return FILTER;
    }

    JndiResourceCollectionFilter(CollectionSettingsRegistry registry) {
        super(registry, INCLD_SETTING, EXCLD_SETTING);

        setExclusionPatterns(DEFAULT_EXCLUSION_PATTERNS);
    }

    void setInclusionPatterns(String... patterns) {
        setInclusionPatterns((ArrayUtil.length(patterns) <= 0) ? Collections.<String>emptyList() : Arrays.asList(patterns));
    }

    void setInclusionPatterns(Collection<String> patterns) {
        setInclusionPattern(combinePatterns(patterns));
    }

    void setExclusionPatterns(String... patterns) {
        setExclusionPatterns((ArrayUtil.length(patterns) <= 0) ? Collections.<String>emptyList() : Arrays.asList(patterns));
    }

    void setExclusionPatterns(Collection<String> patterns) {
        setExclusionPattern(combinePatterns(patterns));
    }

    static final String combinePatterns(Collection<String> patterns) {
        if (ListUtil.size(patterns) <= 0) {
            return "";
        }

        StringBuilder sb = new StringBuilder(patterns.size() * 6);
        for (String p : patterns) {
            if (StringUtil.isEmpty(p)) {
                throw new IllegalArgumentException("Null/empty pattern in " + patterns);
            }

            if (sb.length() > 0) {
                sb.append('|');
            }

            sb.append(".*");
            if (p.charAt(0) == '.') {
                sb.append('\\');
            }
            sb.append(p).append('$');
        }

        return sb.toString();
    }
}