aboutsummaryrefslogtreecommitdiffstats
path: root/sdk/src/java/org/cyanogenmod/internal/util/FileUtils.java
blob: a861b085d9f45ae2d000e1c2d7b7f05115f83653 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
/*
 * Copyright (C) 2016 The CyanogenMod Project
 *
 * 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 org.cyanogenmod.internal.util;

import android.util.Log;

import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.File;
import java.io.FileNotFoundException;
import java.io.FileReader;
import java.io.FileWriter;
import java.io.IOException;

public final class FileUtils {
    private static final String TAG = "FileUtils";

    private FileUtils() {
        // This class is not supposed to be instantiated
    }

    /**
     * Reads the first line of text from the given file.
     * Reference {@link BufferedReader#readLine()} for clarification on what a line is
     *
     * @return the read line contents, or null on failure
     */
    public static String readOneLine(String fileName) {
        String line = null;
        BufferedReader reader = null;

        try {
            reader = new BufferedReader(new FileReader(fileName), 512);
            line = reader.readLine();
        } catch (FileNotFoundException e) {
            Log.w(TAG, "No such file " + fileName + " for reading", e);
        } catch (IOException e) {
            Log.e(TAG, "Could not read from file " + fileName, e);
        } finally {
            try {
                if (reader != null) {
                    reader.close();
                }
            } catch (IOException e) {
                // Ignored, not much we can do anyway
            }
        }

        return line;
    }

    /**
     * Writes the given value into the given file
     *
     * @return true on success, false on failure
     */
    public static boolean writeLine(String fileName, String value) {
        BufferedWriter writer = null;

        try {
            writer = new BufferedWriter(new FileWriter(fileName));
            writer.write(value);
        } catch (FileNotFoundException e) {
            Log.w(TAG, "No such file " + fileName + " for writing", e);
            return false;
        } catch (IOException e) {
            Log.e(TAG, "Could not write to file " + fileName, e);
            return false;
        } finally {
            try {
                if (writer != null) {
                    writer.close();
                }
            } catch (IOException e) {
                // Ignored, not much we can do anyway
            }
        }

        return true;
    }

    /**
     * Checks whether the given file is readable
     *
     * @return true if readable, false if not
     */
    public static boolean isFileReadable(String fileName) {
        final File file = new File(fileName);
        return file.exists() && file.canRead();
    }

    /**
     * Checks whether the given file is writable
     *
     * @return true if writable, false if not
     */
    public static boolean isFileWritable(String fileName) {
        final File file = new File(fileName);
        return file.exists() && file.canWrite();
    }
}