package android.nfc.cardemulation; import java.io.IOException; import java.util.ArrayList; import java.util.List; import org.xmlpull.v1.XmlPullParser; import org.xmlpull.v1.XmlPullParserException; import org.xmlpull.v1.XmlSerializer; import android.os.Parcel; import android.os.Parcelable; import android.util.Log; /** * The AidGroup class represents a group of Application Identifiers (AIDs). * *

The format of AIDs is defined in the ISO/IEC 7816-4 specification. This class * requires the AIDs to be input as a hexadecimal string, with an even amount of * hexadecimal characters, e.g. "F014811481". * * @hide */ public final class AidGroup implements Parcelable { /** * The maximum number of AIDs that can be present in any one group. */ public static final int MAX_NUM_AIDS = 256; static final String TAG = "AidGroup"; final List aids; final String category; final String description; /** * Creates a new AidGroup object. * * @param aids The list of AIDs present in the group * @param category The category of this group, e.g. {@link CardEmulation#CATEGORY_PAYMENT} */ public AidGroup(List aids, String category) { if (aids == null || aids.size() == 0) { throw new IllegalArgumentException("No AIDS in AID group."); } if (aids.size() > MAX_NUM_AIDS) { throw new IllegalArgumentException("Too many AIDs in AID group."); } for (String aid : aids) { if (!CardEmulation.isValidAid(aid)) { throw new IllegalArgumentException("AID " + aid + " is not a valid AID."); } } if (isValidCategory(category)) { this.category = category; } else { this.category = CardEmulation.CATEGORY_OTHER; } this.aids = new ArrayList(aids.size()); for (String aid : aids) { this.aids.add(aid.toUpperCase()); } this.description = null; } AidGroup(String category, String description) { this.aids = new ArrayList(); this.category = category; this.description = description; } /** * @return the category of this AID group */ public String getCategory() { return category; } /** * @return the list of AIDs in this group */ public List getAids() { return aids; } @Override public String toString() { StringBuilder out = new StringBuilder("Category: " + category + ", AIDs:"); for (String aid : aids) { out.append(aid); out.append(", "); } return out.toString(); } @Override public int describeContents() { return 0; } @Override public void writeToParcel(Parcel dest, int flags) { dest.writeString(category); dest.writeInt(aids.size()); if (aids.size() > 0) { dest.writeStringList(aids); } } public static final Parcelable.Creator CREATOR = new Parcelable.Creator() { @Override public AidGroup createFromParcel(Parcel source) { String category = source.readString(); int listSize = source.readInt(); ArrayList aidList = new ArrayList(); if (listSize > 0) { source.readStringList(aidList); } return new AidGroup(aidList, category); } @Override public AidGroup[] newArray(int size) { return new AidGroup[size]; } }; static public AidGroup createFromXml(XmlPullParser parser) throws XmlPullParserException, IOException { String category = null; ArrayList aids = new ArrayList(); AidGroup group = null; boolean inGroup = false; int eventType = parser.getEventType(); int minDepth = parser.getDepth(); while (eventType != XmlPullParser.END_DOCUMENT && parser.getDepth() >= minDepth) { String tagName = parser.getName(); if (eventType == XmlPullParser.START_TAG) { if (tagName.equals("aid")) { if (inGroup) { String aid = parser.getAttributeValue(null, "value"); if (aid != null) { aids.add(aid.toUpperCase()); } } else { Log.d(TAG, "Ignoring tag while not in group"); } } else if (tagName.equals("aid-group")) { category = parser.getAttributeValue(null, "category"); if (category == null) { Log.e(TAG, " tag without valid category"); return null; } inGroup = true; } else { Log.d(TAG, "Ignoring unexpected tag: " + tagName); } } else if (eventType == XmlPullParser.END_TAG) { if (tagName.equals("aid-group") && inGroup && aids.size() > 0) { group = new AidGroup(aids, category); break; } } eventType = parser.next(); } return group; } public void writeAsXml(XmlSerializer out) throws IOException { out.startTag(null, "aid-group"); out.attribute(null, "category", category); for (String aid : aids) { out.startTag(null, "aid"); out.attribute(null, "value", aid); out.endTag(null, "aid"); } out.endTag(null, "aid-group"); } static boolean isValidCategory(String category) { return CardEmulation.CATEGORY_PAYMENT.equals(category) || CardEmulation.CATEGORY_OTHER.equals(category); } }