<commit_before>/*
 * Copyright 2011 <NAME> (heuer[at]semagia.com). 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.semagia.cassa.server.utils;

import java.io.UnsupportedEncodingException;
import java.math.BigInteger;
import java.net.URI;
import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;

import com.semagia.cassa.common.MediaType;
import com.semagia.cassa.common.dm.IGraphInfo;

/**
 * Utility functions to create ETags.
 * 
 * @author <NAME> (heuer[at]semagia.com) <a href="http://www.semagia.com/">Semagia</a>
 */
public final class ETagUtils {

    /**
     * Returns a string which could be used as ETag for the provided graph 
     * and media type combination.
     * 
     * Returns {@code null} if an ETag could not be created.
     * 
     * @param graphInfo {@link IGraphInfo} instance, never {@code null}.
     * @param mediaType {@link MediaType} instance or {@code null}.
     * @return A string which serves as ETag or {@code null}.
     */
    public static String generateETag(final IGraphInfo graphInfo, final MediaType mediaType) {
        return generateETag(graphInfo.getURI(), graphInfo.getLastModification(), mediaType);
    }

    /**
     * Returns a string which could be used as ETag for the provided graph 
     * and media type combination.
     * <commit_msg>Added private constructor to avoid instantiation<commit_after>/*
 * Copyright 2011 <NAME>uer (heuer[at]semagia.com). 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.semagia.cassa.server.utils;

import java.io.UnsupportedEncodingException;
import java.math.BigInteger;
import java.net.URI;
import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;

import com.semagia.cassa.common.MediaType;
import com.semagia.cassa.common.dm.IGraphInfo;

/**
 * Utility functions to create ETags.
 * 
 * @author <NAME> (heuer[at]semagia.com) <a href="http://www.semagia.com/">Semagia</a>
 */
public final class ETagUtils {

    private ETagUtils() {
        // noop.
    }

    /**
     * Returns a string which could be used as ETag for the provided graph 
     * and media type combination.
     * 
     * Returns {@code null} if an ETag could not be created.
     * 
     * @param graphInfo {@link IGraphInfo} instance, never {@code null}.
     * @param mediaType {@link MediaType} instance or {@code null}.
     * @return A string which serves as ETag or {@code null}.
     */
    public static String generateETag(final IGraphInfo graphInfo, final MediaType mediaType) {
        return generateETag(graphInfo.getURI(), graphInfo.getLastModification(), mediaType);
    }

    /**
     * Returns a string which could be used as ETag for the provided graph 
     * and media type combination.
     * 
{'fraction_non_alphanumeric': 0.09535005224660396, 'fraction_numerical': 0.0041797283176593526, 'mean_word_length': 3.4731308411214954, 'pattern_counts': {'":': 0, '<': 11, '<?xml version=': 0, '>': 11, 'https://': 0, 'lorem ipsum': 0, 'www.': 4, 'xml': 0}, 'pii_count': 0, 'substrings_counts': 0, 'word_list_counts': {'cursed_substrings.json': 0, 'profanity_word_list.json': 0, 'sexual_word_list.json': 0, 'zh_pornsignals.json': 0}}
{'dir': 'git-commits-cleaned', 'id': '6037145', 'n_tokens_mistral': 1099, 'n_tokens_neox': 1065, 'n_words': 406}