HSFriendlyNameElement.java revision 74339de52d7066f22771d914e698da503232c107 
1package com.android.server.wifi.hotspot2.anqp;
2
3import com.android.internal.annotations.VisibleForTesting;
4
5import java.net.ProtocolException;
6import java.nio.BufferUnderflowException;
7import java.nio.ByteBuffer;
8import java.nio.charset.StandardCharsets;
9import java.util.ArrayList;
10import java.util.Collections;
11import java.util.List;
12
13/**
14 * The Operator Friendly Name vendor specific ANQP Element,
15 * Wi-Fi Alliance Hotspot 2.0 (Release 2) Technical Specification - Version 5.00,
16 * section 4.3.
17 *
18 * Format:
19 *
20 * | Operator Name Duple #1 (optional) | ...
21 *          variable
22 *
23 * | Operator Name Duple #N (optional) |
24 *             variable
25 */
26public class HSFriendlyNameElement extends ANQPElement {
27    /**
28     * Maximum length for an Operator Name.  Refer to Hotspot 2.0 (Release 2) Technical
29     * Specification section 4.3 for more info.
30     */
31    @VisibleForTesting
32    public static final int MAXIMUM_OPERATOR_NAME_LENGTH = 252;
33
34    private final List<I18Name> mNames;
35
36    @VisibleForTesting
37    public HSFriendlyNameElement(List<I18Name> names) {
38        super(Constants.ANQPElementType.HSFriendlyName);
39        mNames = names;
40    }
41
42    /**
43     * Parse a HSFriendlyNameElement from the given buffer.
44     *
45     * @param payload The buffer to read from
46     * @return {@link HSFriendlyNameElement}
47     * @throws BufferUnderflowException
48     * @throws ProtocolException
49     */
50    public static HSFriendlyNameElement parse(ByteBuffer payload)
51            throws ProtocolException {
52        List<I18Name> names = new ArrayList<I18Name>();
53        while (payload.hasRemaining()) {
54            I18Name name = I18Name.parse(payload);
55            // Verify that the number of bytes for the operator name doesn't exceed the max
56            // allowed.
57            int textBytes = name.getText().getBytes(StandardCharsets.UTF_8).length;
58            if (textBytes > MAXIMUM_OPERATOR_NAME_LENGTH) {
59                throw new ProtocolException("Operator Name exceeds the maximum allowed "
60                        + textBytes);
61            }
62            names.add(name);
63        }
64        return new HSFriendlyNameElement(names);
65    }
66
67    public List<I18Name> getNames() {
68        return Collections.unmodifiableList(mNames);
69    }
70
71    @Override
72    public boolean equals(Object thatObject) {
73        if (this == thatObject) {
74            return true;
75        }
76        if (!(thatObject instanceof HSFriendlyNameElement)) {
77            return false;
78        }
79        HSFriendlyNameElement that = (HSFriendlyNameElement) thatObject;
80        return mNames.equals(that.mNames);
81    }
82
83    @Override
84    public int hashCode() {
85        return mNames.hashCode();
86    }
87
88    @Override
89    public String toString() {
90        return "HSFriendlyName{" +
91                "mNames=" + mNames +
92                '}';
93    }
94}
95