1 /*
2  * Copyright (C) 2014 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.car.internal.util;
18 
19 import android.annotation.NonNull;
20 import android.annotation.Nullable;
21 
22 import com.android.internal.util.Preconditions;
23 
24 import java.io.IOException;
25 
26 // Copied from frameworks/base
27 /**
28  * Utility methods for proxying richer exceptions across Binder calls.
29  *
30  * @hide
31  */
32 public class ExceptionUtils {
33     /** TODO add javadoc */
wrap(IOException e)34     public static RuntimeException wrap(IOException e) {
35         throw new ParcelableException(e);
36     }
37 
38     /** TODO add javadoc */
maybeUnwrapIOException(RuntimeException e)39     public static void maybeUnwrapIOException(RuntimeException e) throws IOException {
40         if (e instanceof ParcelableException) {
41             ((ParcelableException) e).maybeRethrow(IOException.class);
42         }
43     }
44 
45     /** TODO add javadoc */
getCompleteMessage(String msg, Throwable throwable)46     public static String getCompleteMessage(String msg, Throwable throwable) {
47         Throwable t = throwable;
48         final StringBuilder builder = new StringBuilder();
49         if (msg != null) {
50             builder.append(msg).append(": ");
51         }
52         builder.append(t.getMessage());
53         while ((t = t.getCause()) != null) {
54             builder.append(": ").append(t.getMessage());
55         }
56         return builder.toString();
57     }
58 
59     /** TODO add javadoc */
getCompleteMessage(Throwable t)60     public static String getCompleteMessage(Throwable t) {
61         return getCompleteMessage(null, t);
62     }
63 
64     /** TODO add javadoc */
propagateIfInstanceOf( @ullable Throwable t, Class<E> c)65     public static <E extends Throwable> void propagateIfInstanceOf(
66             @Nullable Throwable t, Class<E> c) throws E {
67         if (t != null && c.isInstance(t)) {
68             throw c.cast(t);
69         }
70     }
71 
72     /**
73      * @param <E> a checked exception that is ok to throw without wrapping
74      */
propagate(@onNull Throwable t, Class<E> c)75     public static <E extends Exception> RuntimeException propagate(@NonNull Throwable t, Class<E> c)
76             throws E {
77         propagateIfInstanceOf(t, c);
78         return propagate(t);
79     }
80 
81     /** TODO add javadoc */
propagate(@onNull Throwable t)82     public static RuntimeException propagate(@NonNull Throwable t) {
83         Preconditions.checkNotNull(t);
84         propagateIfInstanceOf(t, Error.class);
85         propagateIfInstanceOf(t, RuntimeException.class);
86         throw new RuntimeException(t);
87     }
88 
89     /**
90      * Gets the root {@link Throwable#getCause() cause} of {@code t}
91      */
getRootCause(@onNull Throwable throwable)92     public static @NonNull Throwable getRootCause(@NonNull Throwable throwable) {
93         Throwable t = throwable;
94         while (t.getCause() != null) t = t.getCause();
95         return t;
96     }
97 
98     /**
99      * Appends {@code cause} at the end of the causal chain of {@code t}
100      *
101      * @return {@code t} for convenience
102      */
appendCause(@onNull Throwable t, @Nullable Throwable cause)103     public static @NonNull Throwable appendCause(@NonNull Throwable t, @Nullable Throwable cause) {
104         if (cause != null) {
105             getRootCause(t).initCause(cause);
106         }
107         return t;
108     }
109 
110 
111 }
112