Package java.lang

Descriptions of modified and extended features included from Java Platform Micro Edition Configurations (CLDC and CDC).

See:
Description

Package java.lang Description

Descriptions of modified and extended features included from Java Platform Micro Edition Configurations (CLDC and CDC). MIDP is designed to be based on either the Connected, Limited Device Configuration [CLDC] or Connected Device Configuration [CDC]. Some features of [CLDC] and [CDC] are modified or extended by MIDP.

System Functions

MIDP requires a set of modified behaviors for certain [CLDC] and [CDC] system functions related to the exit of MIDlets.

System.exit

The behavior of java.lang.System.exit MUST throw a java.lang.SecurityException when invoked by a MIDlet. The only way a MIDlet can indicate that it is complete is by calling MIDlet.notifyDestroyed.

Runtime.exit

The behavior of java.lang.Runtime.exit MUST throw a java.lang.SecurityException when invoked by a MIDlet. The only way a MIDlet can indicate that it is complete is by calling MIDlet.notifyDestroyed.

System Properties

MIDP defines the following property values (in addition to those defined in [CLDC] and [CDC]) that MUST be made available to the application using java.lang.System.getProperty. Other properties may be available from other configurations, profiles, or from the implementation.

Table 10-1 : MIDP 3.0 System Properties
System Property	Description
microedition.deviceid.uuid	A unique hardware device identifier corresponding to a UUID
microedition.deviceid.imei	A unique hardware device identifier corresponding to the device's IMEI
microedition.deviceid.esn	A unique hardware device identifier corresponding to the device's ESN
microedition.deviceid.meid	A unique hardware device identifier corresponding to the device's MEID
microedition.deviceid.pesn	A unique hardware device identifier corresponding to the device's pESN
microedition.subscriberid.uuid	A unique subscriber or user identifier represented by a UUID string
microedition.subscriberid.imsi	A unique subscriber or user identifier corresponding to an IMSI
microedition.subscriberid.msisdn	A unique subscriber or user identifier corresponding to an MSISDN
microedition.subscriberid.iccid	A unique subscriber or user identifier corresponding to an ICCID
microedition.subscriberid.euimid	A unique subscriber or user identifier corresponding to an EUIMID
microedition.locale	The current locale of the device, MUST NOT be null
microedition.profiles	is a blank (Unicode U+0020) separated list of the Java ME profiles that this device supports; this property MUST contain at least "MIDP-3.0"
microedition.platform	Name of the host platform or device
microedition.commports	A comma separated list of available logical serial ports
microedition.hostname	The local hostname (if available)

Device Identifier System Properties

• The microedition.deviceid.uuid property MUST contain a UUID string value that can be used to uniquely identify the device. The format of the value of this property MUST correspond to a Universally Unique Identifier (UUID) as defined in [RFC4122]. This value MUST consist of 32 hexadecimal digits. Implementations SHOULD use UUID version 1 if a 48 bit IEEE address is available; otherwise, implementations SHOULD use version 4 UUID using a randomly or pseudo-randomly generated 48 bit value The value of this property MUST be identical for all concurrently executing or consecutively invoked MIDlets on a device.

• The microedition.deviceid.imei property MAY contain an IMEI string value that can be used to uniquely identify the device. The format of the value of this property, if present, MUST correspond to an International Mobile Station Equipment Identity (IMEI) as defined in [3GPP-TS23.003].

• The microedition.deviceid.esn property MAY contain an ESN string value that can be used to uniquely identify the device. The format of the value of this property, if present, MUST correspond to an Electronic Serial Number (ESN) as defined in [TIA-ESN] and MUST consist of 8 hexadecimal digits.

• The microedition.deviceid.meid property MAY contain an MEID string value that can be used to uniquely identify the device. The format of the value of this property, if present, MUST correspond to a Mobile Equipment Identifier (MEID) as defined in [3GPP2 S.R0048-A] and MUST consist of 14 hexadecimal digits.

• The microedition.deviceid.pesn property MAY contain a pESN string value that can be used to uniquely identify the device. The format of the value of this property, if present, MUST correspond to a Pseudo Electronic Serial Number (pESN) as defined in [3GPP2 X.S0008-0] and MUST consist of 8 hexadecimal digits.

Subscriber Identifier System Properties

• The microedition.subscriberid.uuid property MUST contain a UUID string value that can be used to uniquely identify the current subscriber or user for the device. The format of the value of this property MUST correspond to a Universally Unique Identifier (UUID) as defined in [RFC4122]. This value MUST consist of 32 hexadecimal digits. Implementations SHOULD use UUID version 1 if a 48 bit IEEE address is available; otherwise, implementations SHOULD use version 4 UUID using a randomly or pseudo-randomly generated 48 bit value The value of this property MUST be identical for all concurrently executing or consecutively invoked MIDlets on a device.

• The microedition.deviceid.imsi property MAY contain an IMSI string value that can be used to uniquely identify the current subscriber or user for the device. The format of the value of this property, if present, MUST correspond to an International Mobile Subscriber Identity (IMSI) as defined in [3GPP-TS23.003].

• The microedition.deviceid.msisdn property MAY contain an MSISDN string value that can be used to uniquely identify the current subscriber or user for the device. The format of the value of this property, if present, MUST correspond to a Mobile Station International PSTN/ISDN Number (MSISDN) as defined in [3GPP-TS24.008].

• The microedition.deviceid.iccid property MAY contain an ICCID string value that can be used to uniquely identify the current subscriber or user for the device. The format of the value of this property, if present, MUST correspond to an Integrated Circuit Card ID (ICCID) as defined in [ITU-T-E.118].

• The microedition.deviceid.euimid property MAY contain an EUIMID string value that can be used to uniquely identify the current subscriber or user for the device. The format of the value of this property, if present, MUST correspond to either a Short Form Expanded User Identity Module Identifier (SF_EUIMID) or a Long Form Expanded User Identity Module Identifier (LF_EUIMID) as defined in [3GPP2-C.S0023-C].

microedition.locale

The microedition.locale property MUST include at least the language code, and SHOULD also include the country code, followed by an OPTIONAL variant, separated by "-" (Unicode U+002D). For example, fr-FR or en-US or zh-CN-Hans.

The language codes MUST be the lower-case, two-letter codes as defined by ISO 639-1:2002.

The country codes MUST be the upper-case, two-letter codes as defined by ISO 3166-1:1997.

(Note: the MIDP 1.0 specification used the HTTP formatting of language tags as defined in [RFC3066], Tags for the Identification of Languages. This is different from the Java SE definition for java.util.Locale printed strings where fields are separated by "_" (Unicode U+005F).)

microedition.profiles

The microedition.profiles system property MUST NOT contain different versions of the same profile. In particular, MIDP-1.0 and MIDP-2.x MUST NOT be listed, only MIDP-3.0.

microedition.platform

The value of the microedition.platform system property MUST conform to the following syntax :

    Manufacturer_name
    Device_model_identifier
    “/”version_identifier
    [“/”additional_comments ]
                    

Manufacturer name and device model number are mandatory and MUST be concatenated without spaces between them. Optional additional comments MAY be present. The version identifier and optional additional comments MUST be separated from the rest of the string with a forward slash (/). The value of the property MUST NOT contain any forward slash (/) characters other than those that are used to separate the version number and additional comments from the rest of the information.

microedition.commports

The value of the microedition.commports system property MUST contain a comma separated list of available logical port names, any of which can be combined with a comm: prefix as the URL string to be used to open a serial port connection. See CommConnection for more information.

microedition.hostname

The value of the microedition.hostname system property MUST contain the host name of the local device, if it is available.

Application Resource Files

Application resource files are accessed using getResourceAsStream(String name) in java.lang.Class. In the MIDP specification, getResourceAsStream is used to allow resource files to be retrieved from MIDlet suite and LIBlet JAR files.

Resource names refer to the contents of a MIDlet Suite or LIBlet JAR. Absolute pathnames, beginning with "/" are fully qualified file names within the JAR. The resource file is loaded from the same context as the Class instance it is called upon. Only a single JAR is searched for the resource. For example, if called on a class loaded from the MIDlet Suite, the resource will be retrieved from the MIDlet Suite JAR.

Relative pathnames, not beginning with "/" are relative to the class upon which getResourceAsStream is called. Relative names are converted to absolute by prepending a "/" followed by the fully qualified package with "." characters converted to "/" and a separator of "/". The resulting string is reduced to canonical form by applying as many times as possible the following:

• All occurrences of "/./" are replaced with "/".
• All occurrences of "/segment/../" are replaced with "/" where segment does not contain "/".

The canonical resource name is the absolute pathname of the resource within the JAR.

In no case can the path extend outside the JAR, and resources outside the JAR MUST NOT be accessible. For example, using "../../" does NOT point outside the JAR. If there are any remaining "." or ".." characters they are treated literally in locating the resource. No resource can exist with that name so null is returned from Class.getResourceAsStream. Also, devices SHOULD NOT allow class files to be read from the JAR as resources, but all other files MUST be accessible.

Since:

MIDP 1.0