FileDocCategorySizeDatePackage
RssiCurve.javaAPI DocAndroid 5.1 API8227Thu Mar 12 22:22:10 GMT 2015android.net

RssiCurve

public class RssiCurve extends Object implements android.os.Parcelable
A curve defining the network score over a range of RSSI values.

For each RSSI bucket, the score may be any byte. Scores have no absolute meaning and are only considered relative to other scores assigned by the same scorer. Networks with no score are treated equivalently to a network with score {@link Byte#MIN_VALUE}, and will not be used.

For example, consider a curve starting at -110 dBm with a bucket width of 10 and the following buckets: {@code [-20, -10, 0, 10, 20, 30, 40, 50, 60, 70, 80, 90, 100, 110, 120]}. This represents a linear curve between -110 dBm and 30 dBm. It scores progressively higher at stronger signal strengths.

A network can be assigned a fixed score independent of RSSI by setting {@link #rssiBuckets} to a one-byte array whose element is the fixed score. {@link #start} should be set to the lowest RSSI value at which this fixed score should apply, and {@link #bucketWidth} should be set such that {@code start + bucketWidth} is equal to the highest RSSI value at which this fixed score should apply.

Note that RSSI values below -110 dBm or above 30 dBm are unlikely to cause any difference in connectivity behavior from those endpoints. That is, the connectivity framework will treat a network with a -120 dBm signal exactly as it would treat one with a -110 dBm signal. Therefore, graphs which specify scores outside this range may be truncated to this range by the system.

see
ScoredNetwork
hide

Fields Summary
private static final int
DEFAULT_ACTIVE_NETWORK_RSSI_BOOST
public final int
start
The starting dBm of the curve.
public final int
bucketWidth
The width of each RSSI bucket, in dBm.
public final byte[]
rssiBuckets
The score for each RSSI bucket.
public final int
activeNetworkRssiBoost
The RSSI boost to give this network when active, in dBm.

When the system is connected to this network, it will pretend that the network has this much higher of an RSSI. This is to avoid switching networks when another network has only a slightly higher score.

public static final Creator
CREATOR
Constructors Summary
public RssiCurve(int start, int bucketWidth, byte[] rssiBuckets)
Construct a new {@link RssiCurve}.

param
start the starting dBm of the curve.
param
bucketWidth the width of each RSSI bucket, in dBm.
param
rssiBuckets the score for each RSSI bucket.


                                        
           
        this(start, bucketWidth, rssiBuckets, DEFAULT_ACTIVE_NETWORK_RSSI_BOOST);
public RssiCurve(int start, int bucketWidth, byte[] rssiBuckets, int activeNetworkRssiBoost)
Construct a new {@link RssiCurve}.

param
start the starting dBm of the curve.
param
bucketWidth the width of each RSSI bucket, in dBm.
param
rssiBuckets the score for each RSSI bucket.
param
activeNetworkRssiBoost the RSSI boost to apply when this network is active, in dBm.

        this.start = start;
        this.bucketWidth = bucketWidth;
        if (rssiBuckets == null || rssiBuckets.length == 0) {
            throw new IllegalArgumentException("rssiBuckets must be at least one element large.");
        }
        this.rssiBuckets = rssiBuckets;
        this.activeNetworkRssiBoost = activeNetworkRssiBoost;
private RssiCurve(android.os.Parcel in)

        start = in.readInt();
        bucketWidth = in.readInt();
        int bucketCount = in.readInt();
        rssiBuckets = new byte[bucketCount];
        in.readByteArray(rssiBuckets);
        activeNetworkRssiBoost = in.readInt();
Methods Summary
public intdescribeContents()

        return 0;
public booleanequals(java.lang.Object o)
Determine if two RSSI curves are defined in the same way.

Note that two curves can be equivalent but defined differently, e.g. if one bucket in one curve is split into two buckets in another. For the purpose of this method, these curves are not considered equal to each other.

        if (this == o) return true;
        if (o == null || getClass() != o.getClass()) return false;

        RssiCurve rssiCurve = (RssiCurve) o;

        return start == rssiCurve.start &&
                bucketWidth == rssiCurve.bucketWidth &&
                Arrays.equals(rssiBuckets, rssiCurve.rssiBuckets) &&
                activeNetworkRssiBoost == rssiCurve.activeNetworkRssiBoost;
public inthashCode()

        return Objects.hash(start, bucketWidth, rssiBuckets, activeNetworkRssiBoost);
public bytelookupScore(int rssi)
Lookup the score for a given RSSI value.

param
rssi The RSSI to lookup. If the RSSI falls below the start of the curve, the score at the start of the curve will be returned. If it falls after the end of the curve, the score at the end of the curve will be returned.
return
the score for the given RSSI.

        return lookupScore(rssi, false /* isActiveNetwork */);
public bytelookupScore(int rssi, boolean isActiveNetwork)
Lookup the score for a given RSSI value.

param
rssi The RSSI to lookup. If the RSSI falls below the start of the curve, the score at the start of the curve will be returned. If it falls after the end of the curve, the score at the end of the curve will be returned.
param
isActiveNetwork Whether this network is currently active.
return
the score for the given RSSI.

        if (isActiveNetwork) {
            rssi += activeNetworkRssiBoost;
        }

        int index = (rssi - start) / bucketWidth;

        // Snap the index to the closest bucket if it falls outside the curve.
        if (index < 0) {
            index = 0;
        } else if (index > rssiBuckets.length - 1) {
            index = rssiBuckets.length - 1;
        }

        return rssiBuckets[index];
public java.lang.StringtoString()

        StringBuilder sb = new StringBuilder();
        sb.append("RssiCurve[start=")
                .append(start)
                .append(",bucketWidth=")
                .append(bucketWidth)
                .append(",activeNetworkRssiBoost=")
                .append(activeNetworkRssiBoost);

        sb.append(",buckets=");
        for (int i = 0; i < rssiBuckets.length; i++) {
            sb.append(rssiBuckets[i]);
            if (i < rssiBuckets.length - 1) {
                sb.append(",");
            }
        }
        sb.append("]");

        return sb.toString();
public voidwriteToParcel(android.os.Parcel out, int flags)

        out.writeInt(start);
        out.writeInt(bucketWidth);
        out.writeInt(rssiBuckets.length);
        out.writeByteArray(rssiBuckets);
        out.writeInt(activeNetworkRssiBoost);