1 /* 2 * Licensed to the Apache Software Foundation (ASF) under one or more 3 * contributor license agreements. See the NOTICE file distributed with 4 * this work for additional information regarding copyright ownership. 5 * The ASF licenses this file to You under the Apache License, Version 2.0 6 * (the "License"); you may not use this file except in compliance with 7 * the License. You may obtain a copy of the License at 8 * 9 * http://www.apache.org/licenses/LICENSE-2.0 10 * 11 * Unless required by applicable law or agreed to in writing, software 12 * distributed under the License is distributed on an "AS IS" BASIS, 13 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 14 * See the License for the specific language governing permissions and 15 * limitations under the License. 16 */ 17 package org.apache.tika.detect; 18 19 import java.io.InputStream; 20 21 import org.apache.tika.metadata.Metadata; 22 import org.apache.tika.mime.MediaType; 23 24 /** 25 * Content type detection based on a content type hint. This detector simply 26 * trusts any valid content type hint given in the input metadata, and returns 27 * that as the likely type of the input document. 28 * 29 * @since Apache Tika 0.3 30 */ 31 public class TypeDetector implements Detector { 32 33 /** 34 * Detects the content type of an input document based on a type hint 35 * given in the input metadata. The CONTENT_TYPE attribute of the given 36 * input metadata is expected to contain the type of the input document. 37 * If that attribute exists and contains a valid type name, then that 38 * type is returned. 39 * 40 * @param input ignored 41 * @param metadata input metadata, possibly with a CONTENT_TYPE value 42 * @return detected media type, or <code>application/octet-stream</code> 43 */ 44 public MediaType detect(InputStream input, Metadata metadata) { 45 // Look for a type hint in the input metadata 46 String hint = metadata.get(Metadata.CONTENT_TYPE); 47 if (hint != null) { 48 MediaType type = MediaType.parse(hint); 49 if (type != null) { 50 return type; 51 } 52 } 53 return MediaType.OCTET_STREAM; 54 } 55 56 }