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DataElement.javaAPI DocphoneME MR2 API (J2ME)11259Wed May 02 18:00:30 BST 2007javax.bluetooth

DataElement

public class DataElement extends Object
This class is defined by the JSR-82 specification Java™ APIs for Bluetooth™ Wireless Technology, Version 1.1.

Fields Summary
public static final int
NULL
public static final int
U_INT_1
public static final int
U_INT_2
public static final int
U_INT_4
public static final int
U_INT_8
public static final int
U_INT_16
public static final int
INT_1
public static final int
INT_2
public static final int
INT_4
public static final int
INT_8
public static final int
INT_16
public static final int
URL
public static final int
UUID
public static final int
BOOL
public static final int
STRING
public static final int
DATSEQ
public static final int
DATALT
private int
valueType
Keeps the specified or derived type of the element.
private boolean
booleanValue
Keeps the boolean value for the type BOOL.
private long
longValue
Keeps the long value for the types *INT*.
private Object
miscValue
Keeps the misc type value for the rest of types. This field also keeps the value for the type DATALT and DATSEQ. In this case it's a Vector. The access to the Vector elements is synchronized in cldc (according the source code). But, this is not documented, so we make a synchronize access to this field to fit any cldc implementation.
Constructors Summary
public DataElement(int valueType)


    // JAVADOC COMMENT ELIDED 
       
        switch (valueType) {
        case NULL: /* miscValue = null in this case. */
            break;
        case DATALT: /* falls through */
        case DATSEQ:
            this.miscValue = new Vector();
            break;
        default:
            throw new IllegalArgumentException(
                    "Invalid valueType for this constructor: " + valueType);
        }
        this.valueType = valueType;
public DataElement(boolean bool)

        valueType = BOOL;
        booleanValue = bool;
public DataElement(int valueType, long value)

        long min = 0;
        long max = 0;

        switch (valueType) {
        case U_INT_1:
            max = 0xffL;
            break;
        case U_INT_2:
            max = 0xffffL;
            break;
        case U_INT_4:
            max = 0xffffffffL;
            break;
        case INT_1:
            min = Byte.MIN_VALUE;
            max = Byte.MAX_VALUE;
            break;
        case INT_2:
            min = -0x8000L;
            max = 0x7fffL;
            break;
        case INT_4:
            min = Integer.MIN_VALUE;
            max = Integer.MAX_VALUE;
            break;
        case INT_8:
            min = Long.MIN_VALUE;
            max = Long.MAX_VALUE;
            break;
        default:
            throw new IllegalArgumentException(
                    "Invalid 'valueType' for this constructor: " + valueType);
        }

        // check if value in the valid rangle for this type
        if (value < min || value > max) {
            throw new IllegalArgumentException(
                    "Invalid 'value' for specified type: " + value);
        }
        this.valueType = valueType;
        this.longValue = value;
public DataElement(int valueType, Object value)

        boolean isCorrectValue = true;

        switch (valueType) {
        case URL: /* falls through */
        case STRING:
            isCorrectValue = value instanceof String;
            break;
        case UUID:
            isCorrectValue = value instanceof UUID;
            break;
        case INT_16: /* falls through */
        case U_INT_16:
            isCorrectValue = value instanceof byte[]
                    && ((byte[]) value).length == 16;
            break;
        case U_INT_8:
            isCorrectValue = value instanceof byte[]
                    && ((byte[]) value).length == 8;
            break;
        default:
            throw new IllegalArgumentException(
                    "Invalid 'valueType' for this constructor: " + valueType);
        }

        // check if value in the valid rangle for this type
        if (!isCorrectValue) {
            throw new IllegalArgumentException(
                    "Invalid 'value' for specified type: " + value);
        }
        this.valueType = valueType;
        this.miscValue = value;
Methods Summary
public synchronized voidaddElement(javax.bluetooth.DataElement elem)


        /*
         * We can't optimize this by invoking the
         * this.insertElementAt(elem, getSize()), because
         * the ClassCastException may be thrown from getSize()
         * which gives us improper stack trace.
         */
        if (valueType != DATSEQ && valueType != DATALT) {
            throw new ClassCastException(
                    "Invalid element type for this method: " + valueType);
        }

        if (elem == null) {
            throw new NullPointerException("Specified element is null");
        }
        ((Vector) miscValue).addElement(elem);
public booleangetBoolean()

        if (valueType != BOOL) {
            throw new ClassCastException(
                    "Invalid element type for this method: " + valueType);
        }
        return booleanValue;
public intgetDataType()

        return valueType;
public longgetLong()

        switch (valueType) {
        case U_INT_1: /* falls through */
        case U_INT_2: /* falls through */
        case U_INT_4: /* falls through */
        case INT_1: /* falls through */
        case INT_2: /* falls through */
        case INT_4: /* falls through */
        case INT_8:
            break;
        default:
            throw new ClassCastException(
                    "Invalid element type for this method: " + valueType);
        }
        return longValue;
public synchronized intgetSize()

        if (valueType != DATSEQ && valueType != DATALT) {
            throw new ClassCastException(
                    "Invalid element type for this method: " + valueType);
        }
        return ((Vector) miscValue).size();
public synchronized java.lang.ObjectgetValue()

        Object retValue = miscValue;

        /*
         * According to cldc & bluetooth specifications, the String and UUID
         * are immutable, so we may not return a clone object to safe
         * the stored one.
         *
         * The Vector.elements() returns an Enumeration, which does not allow
         * to break the Vector either.
         *
         * The array may be modified by reference, so we have to return
         * a clone.
         */
        switch (valueType) {
        case URL: /* falls through */
        case STRING: /* falls through */
        case UUID:
            break;
        case DATALT: /* falls through */
        case DATSEQ:
            retValue = ((Vector) miscValue).elements();
            break;
        case U_INT_8: /* falls through */
        case U_INT_16: /* falls through */
        case INT_16:
            int length = ((byte[]) miscValue).length;
            retValue = new byte[length];
            System.arraycopy(miscValue, 0, retValue, 0, length);
            break;
        default:
            throw new ClassCastException(
                    "Invalid element type for this method: " + valueType);
        }
        return retValue;
public synchronized voidinsertElementAt(javax.bluetooth.DataElement elem, int index)

        if (valueType != DATSEQ && valueType != DATALT) {
            throw new ClassCastException(
                    "Invalid element type for this method: " + valueType);
        }

        if (elem == null) {
            throw new NullPointerException("Specified element is null");
        }

        /*
         * We can't use the Vector.insertElementAt check for out of
         * bounds, because Vector throws ArrayIndexOutOfBoundsException
         * in this case.
         */
        if (index < 0 || index > ((Vector) miscValue).size()) {
            throw new IndexOutOfBoundsException(
                    "Specified index is out of range");
        }
        ((Vector) miscValue).insertElementAt(elem, index);
public booleanremoveElement(javax.bluetooth.DataElement elem)

        if (valueType != DATSEQ && valueType != DATALT) {
            throw new ClassCastException(
                    "Invalid element type for this method: " + valueType);
        }

        if (elem == null) {
            throw new NullPointerException("Specified element is null");
        }

        /*
         * The Bluetooth spec says the two DataElement equals if their
         * references are equal. According to cldc1.1 ref impl sources,
         * the Vector uses 'equals' call, and the Object.equls uses
         * a references compare, so we may not care about doing this here.
         */
        return ((Vector) miscValue).removeElement(elem);