log4j-taglib/src/main/java/org/apache/logging/log4j/taglib/EntryTag.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.logging.log4j.taglib;

import java.util.ArrayList;
import java.util.List;

import javax.servlet.jsp.JspException;
import javax.servlet.jsp.tagext.DynamicAttributes;
import javax.servlet.jsp.tagext.Tag;

import org.apache.logging.log4j.Level;

/**
 * This class implements the {@code <log:entry>} tag.
 *
 * @since 2.0
 */
public class EntryTag extends LoggerAwareTagSupport implements DynamicAttributes {
    private static final long serialVersionUID = 1L;

    private static final String FQCN = EntryTag.class.getName();

    private List<Object> attributes;

    @Override
    protected void init() {
        super.init();
        if (this.attributes == null) {
            this.attributes = new ArrayList<>();
        } else {
            this.attributes.clear();
        }
    }

    @Override
    public void setDynamicAttribute(final String uri, final String name, final Object value) {
        this.attributes.add(value);
    }

    @Override
    public int doEndTag() throws JspException {
        final Log4jTaglibLogger logger = this.getLogger();

        if (TagUtils.isEnabled(logger, Level.TRACE, null)) {
            if (this.attributes.size() == 0) {
                logger.entry(FQCN);
            } else {
                logger.entry(FQCN, this.attributes.toArray());
            }
        }

        return Tag.EVAL_PAGE;
    }
}