1 /*
2  * Copyright (C) 2021 The Android Open Source Project
3  *
4  * Licensed under the Apache License, Version 2.0 (the "License");
5  * you may not use this file except in compliance with the License.
6  * You may obtain a copy of the License at
7  *
8  *      http://www.apache.org/licenses/LICENSE-2.0
9  *
10  * Unless required by applicable law or agreed to in writing, software
11  * distributed under the License is distributed on an "AS IS" BASIS,
12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13  * See the License for the specific language governing permissions and
14  * limitations under the License.
15  */
16 
17 package com.android.annotationvisitor;
18 
19 import org.apache.bcel.classfile.ClassParser;
20 import org.apache.bcel.classfile.JavaClass;
21 
22 import java.io.IOException;
23 import java.util.Objects;
24 import java.util.stream.Stream;
25 import java.util.zip.ZipEntry;
26 import java.util.zip.ZipFile;
27 
28 /**
29  * Reads {@link JavaClass} members from a zip/jar file, providing a stream of them for processing.
30  * Any errors are reported via {@link Status#error(Throwable)}.
31  */
32 public class JarReader {
33 
34     private final Status mStatus;
35     private final String mFileName;
36     private final ZipFile mZipFile;
37 
JarReader(Status s, String filename)38     public JarReader(Status s, String filename) throws IOException {
39         mStatus = s;
40         mFileName = filename;
41         mZipFile = new ZipFile(mFileName);
42     }
43 
openZipEntry(ZipEntry e)44     private JavaClass openZipEntry(ZipEntry e) {
45         try {
46             mStatus.debug("Reading %s from %s", e.getName(), mFileName);
47             return new ClassParser(mZipFile.getInputStream(e), e.getName()).parse();
48         } catch (IOException ioe) {
49             mStatus.error(ioe);
50             return null;
51         }
52     }
53 
54 
stream()55     public Stream<JavaClass> stream() {
56         return mZipFile.stream()
57                 .filter(zipEntry -> zipEntry.getName().endsWith(".class"))
58                 .map(zipEntry -> openZipEntry(zipEntry))
59                 .filter(Objects::nonNull);
60     }
61 
close()62     public void close() throws IOException {
63         mZipFile.close();
64     }
65 }
66