Module ibm.jzos
Package com.ibm.jzos

Class ZUtil

java.lang.Object
com.ibm.jzos.ZUtil
public class ZUtil extends Object
This class provides a static interface to various z/OS native library calls, other than I/O.

  • Field Details

  • Method Details

    • getDefaultPlatformEncoding

      public static String getDefaultPlatformEncoding()
      Get the default platform encoding for this instance of the JVM. The encoding is generally some variant of EBCDIC.

      The default value is the Java codepage that matches the default locale encoding for the z/OS Unix process running the JVM, or "IBM-1047" if no matching Java encoding can be found.

      Returns:
      the default output encoding
      See Also:

    • setDefaultPlatformEncoding

      public static void setDefaultPlatformEncoding(String encoding) throws UnsupportedEncodingException
      Set the default output encoding for this instance of the JVM. The encoding is generally some variant of EBCDIC.

      The default value is the Java codepage that matches the default locale encoding for the z/OS Unix process running the JVM, or "IBM-1047" if no matching Java encoding can be found.

      Note: This method should be used with caution, and is generally not recommended for customer use.

      Parameters:
      encoding - the charset encoding to use as a default
      Throws:
      UnsupportedEncodingException - if the encoding is not supported

    • environ

      public static String[] environ()
      Get an array of strings that represent the environment variables of the current process.

      This method reads and returns the values held in the C-library 'environ' global.

      Returns:
      an array of environment variable strings in name=value format

    • getEnvironment

      public static Properties getEnvironment()
      Return a Properties object containing the current process environment variables.
      Since:
      2.1.0

    • getEnv

      public static String getEnv(String varName)
      Get the value of the Environment variable.

      This method calls the getenv() C-library routine.

      Parameters:
      varName - the name of the environment variable
      Returns:
      the value of the environment variable. Null if not found.

    • setEnv

      public static void setEnv(String varName, String varValue) throws ErrnoException
      Set an Environment variable.

      This method calls the setenv() C-library routine.

      Parameters:
      varName - the name of the environment variable
      varValue - the value of the environment variable
      Throws:
      ErrnoException - if the native call fails.
      Since:
      2.1.0

    • getCurrentJobname

      public static String getCurrentJobname()
      Get the current MVS jobname, blanks trimmed
      Returns:
      the jobname

    • getCurrentTsoPrefix

      public static String getCurrentTsoPrefix()
      Gets the TSO prefix, if running under TSO.
      Returns:
      the TSO prefix; null if not running under TSO; an empty string if under TSO with no prefix

    • getCurrentStepname

      public static String getCurrentStepname()
      Get the current MVS stepname, blanks trimmed. This is the "jobstep name" if running under a proc.
      Returns:
      the proc stepname

    • getCurrentProcStepname

      public static String getCurrentProcStepname()
      Get the current MVS proc stepname, blanks trimmed. This is an empty string if not running in a proc.
      Returns:
      the proc stepname

    • getCurrentStepNumber

      public static String getCurrentStepNumber()
      Get the current MVS step number, blanks trimmed
      Returns:
      the step number

    • getCurrentJobId

      public static String getCurrentJobId()
      Get the current MVS jobid, blanks trimmed
      Returns:
      the jobid (job number)

    • getCurrentJobCorrelator

      public static String getCurrentJobCorrelator()
      Get the current MVS job correlator, blanks trimmed
      Returns:
      the job correlator

    • getCurrentJobEntry

      public static long getCurrentJobEntry()
      Get the current Job Entry
      Returns:
      the job entry

    • getCurrentJobEDate

      public static int getCurrentJobEDate()
      Get the current Job Entry Date
      Returns:
      the job entry date

    • getCurrentTimeMicros

      public static long getCurrentTimeMicros()
      Gets the current time, expressed in microseconds since 00:00:00 Coordinated Universal Time (UTC), January 1, 1970

      This function uses the gettimeofday64() C library function, which returns a 64-bit number of seconds since 1/1/1970, and the fractional microseconds as a 32 bit number.

      Returns:
      a (64-bit) Java long containing the number of microseconds since UTC January 1, 1970.
      Since:
      2.1.0, 2.4.8 Changed to use gettimeofday64() to avoid year 2038 overflows

    • getCpuTimeMicros

      public static long getCpuTimeMicros() throws RcException
      Gets the amount of CPU time consumed, expressed in microseconds, for the current thread.

      This function calls the TIMEUSED ECT=COND system macro. Refer to the z/OS MVS Programming: Authorized Assembler Services Reference SET-WTO, SA22-7612 for more information on the TIMEUSED macro.

      Returns:
      a Java long containing the number of microseconds of CPU time consumed by the current thread
      Throws:
      an - (unchecked) RcException if call fails (not expected)
      RcException
      Since:
      2.1.0

    • getEpochMillis

      public static long getEpochMillis(byte[] stckOrStcke) throws RcException
      Get the Unix Epoch milliseconds equivalent to the input STCK time in bytes.

      This function converts a timestamp in STCK byte array to Epoch milliseconds. The returned value is of the same type used by Java for time values, c.f. System.currentTimeMillis().

      Parameters:
      stckOrStcke - 8-byte timestamp in STCK format or 16-byte STCKE format
      Returns:
      a Java long containing time in Epoch milliseconds
      Throws:
      IllegalArgumentException - if stck is null or is not 8 bytes long
      RcException
      Since:
      2.4.5, 2.4.8 Added support for stcke format

    • getEpochMillis

      public static long getEpochMillis(long stck)
      Get the Unix Epoch milliseconds equivalent to the input STCK time in long value.

      This function converts a timestamp in STCK byte array to Epoch milliseconds. The returned value is of the same type used by Java for time values, c.f. System.currentTimeMillis().

      Parameters:
      stck - a STCK timestamp in long
      Returns:
      a Java long containing time in Epoch milliseconds
      Since:
      2.4.5

    • getEpochMilliSeconds

      public static final long getEpochMilliSeconds(long stck)
      Get the Unix Epoch milliseconds equivalent to the input STCK time in long value.

      Note: this is equivalent to getEpochMillis(long)

      This function converts a timestamp in STCK byte array to Epoch milliseconds.

      Parameters:
      stck - a STCK timestamp in long
      Returns:
      a Java long containing time in Epoch milliseconds
      Since:
      2.4.5

    • toInstant

      public static final Instant toInstant(long stck)
      Convert the given z-Architecture TOD clock to a java.time.Instant, which represents the time in Java epoch seconds and nanoseconds within the second.
      Parameters:
      stck - a long representing the 8 byte z-architecture TOD clock value.
      Since:
      2.4.8
      See Also:

    • toInstant

      public static final Instant toInstant(byte[] stckOrStcke)
      Convert the given z-Architecture TOD clock or extended TOD clock value to a java.time.Instant, which represents the time in Java epoch seconds and nanoseconds within the second.
      Parameters:
      stckOrStcke - the 8 or 16 byte z-architecture clock value.
      Since:
      2.4.8
      See Also:

    • getCurrentUser

      public static String getCurrentUser() throws RcException
      Get the current MVS userid.

      This is a convenience method that simply delegates to PlatformThread.getUserName()

      Returns:
      the current MVS userid
      Throws:
      RcException
      See Also:

    • getJavaVersionInfo

      public static String getJavaVersionInfo()
      Get a multi-line string that contains information about the version of Java that is currently running. This method is called by the JZOS batch launcher to display the Java version information on the //SYSOUT DD
      Returns:
      a String in the general form specified by sun.misc.Version.print()

    • getJzosJarVersion

      public static String getJzosJarVersion()
      Load the build_version.properties class resource and return a string representing the version of the JZOS Java archive.

    • getJzosDllVersion

      public static String getJzosDllVersion()
      Return a string representing the version of the JZOS shared library.

    • peekOSMemory

      public static long peekOSMemory(long address, int len) throws RcException
      Peek (read) a long from OS memory.

      Parameters:
      address - the address of the OS memory to start peeking from.
      len - the number of bytes to read into the returned long, must be <= 8
      Throws:
      RcException - if there is an error accessing the memory location.
      IllegalArgumentException - if len > 8 or len <=0
      SecurityException - if a a SecurityManager is active and the user doesn't have access to JzosPermission("peekOSMemory")

    • peekOSMemory

      public static void peekOSMemory(long address, byte[] bytes) throws RcException
      Peek bytes from OS memory.

      Parameters:
      address - the address of the OS memory to start peeking from.
      bytes - the location to store the bytes peeked, for bytes.length
      Throws:
      RcException - if there is an error accessing the memory location.
      SecurityException - if a a SecurityManager is active and the user doesn't have access to JzosPermission("peekOSMemory")

    • peekOSMemory

      public static void peekOSMemory(long address, byte[] bytes, int offset, int len) throws RcException
      Peek bytes from OS memory.
      Parameters:
      address - the address of the OS memory to start peeking from.
      bytes - the location to store the bytes peeked
      offset - the 0-based offset into bytes where to store the first byte peeked
      len - the number of bytes to copy from memory
      Throws:
      IllegalArgumentException - if offset and len are incompatible with bytes
      RcException - if there is an error accessing the memory location.
      SecurityException - if a a SecurityManager is active and the user doesn't have access to JzosPermission("peekOSMemory")

    • logDiagnostic

      public static void logDiagnostic(int level, String msg)
      Send a message to the JZOS toolkit's log, which goes to the Language Environment messages file, which is usually stderr or DD SYSOUT.

      Note: This method is not intended to be used from customer code.

      Parameters:
      level - one of the LOG_XXX constants. If an invalid value is supplied, the message is ignored.
      msg - the message text

    • redirectStandardStreams

      public static void redirectStandardStreams() throws Exception
      Redirect the standard streams using the default platform character encoding.

      The JZOS batch launcher calls this method on startup to cause System.out, System.err and System.in to be directed to/from the job stream. Customers may also wish to use this method for the same purpose when Java is invoked without using the JZOS batch launcher. For example: from a COBOL main program that invokes Java code.

      The I/O for will be redirected to DD:STDIN, DD:STDOUT, and DD:STDERR, using the same EBCDIC encoding that is specified by getDefaultPlatformEncoding(). These DDs must be allocated prior to calling this method, except that DD:SYSIN is optional. If the system property jzos.merge.sysout is set to true, System.out and System.err are redirected to DD:SYSOUT rather than DD:STDOUT and DD:STDERR respectively.

      This facility may only be used to redirect standard streams once, otherwise the results are not predictable.

      Throws:
      Exception - if the streams could not be redirected.
      See Also:

    • redirectStandardStreams

      public static boolean redirectStandardStreams(String requestedEncoding, boolean enableTranscoding) throws Exception
      A static method which redirects the standard streams as follows:
      • System.out is redirected to DD:STDOUT (required)
      • System.err is redirected to DD:STDERR (required)
      • System.in is redirected from DD:STDIN (optional)

      This method is invoked by the JZOS batch launcher to redirect the standard Java streams to MVS DDs. If STDIN is not defined, System.in is set to an InputStream that immediately returns -1 (EOS).

      This facility may only be used to redirect standard streams once, and is NOT intended to be used from customer code.

      If the system property jzos.merge.sysout is set to true, System.out and System.err are redirected to DD:SYSOUT rather than DD:STDOUT and DD:STDERR respectively.

      Parameters:
      requestedEncoding - the requested character encoding. If this encoding is not supported, defaultPlatformEncoding is used.
      Returns:
      true if the requestedEncoding was used, false if the default was used.
      Throws:
      Exception - if the streams could not be redirected.
      See Also:

    • newEncodedPrintStream

      public static PrintStream newEncodedPrintStream(OutputStream os, boolean autoFlush) throws UnsupportedEncodingException
      Construct a PrintStream which is configured to transcode from the current Java file encoding to the current default platform encoding.

      The current Java file encoding can be obtained from the "file.encoding" System property.

      Parameters:
      os - the stream to base the PrintStream on.
      autoFlush - whether or not to autoFlush.
      Returns:
      the printStream
      Throws:
      UnsupportedEncodingException
      See Also:

    • newEncodedPrintStream

      public static PrintStream newEncodedPrintStream(OutputStream os, boolean autoFlush, String encoding) throws UnsupportedEncodingException
      Construct a PrintStream which is configured to transcode from the current Java file encoding to the given encoding.

      The current Java file encoding can be obtained from the "file.encoding" System property.

      Parameters:
      os - the stream to base the PrintStream on.
      autoFlush - whether or not to autoFlush
      encoding - the target charset encoding to use
      Returns:
      the printStream
      Throws:
      UnsupportedEncodingException
      See Also:

    • newEncodedPrintStream

      public static PrintStream newEncodedPrintStream(OutputStream os, boolean autoFlush, String encoding, boolean enable) throws UnsupportedEncodingException
      Construct a PrintStream which which can be used to transcode characters and bytes from the current Java file encoding to the given encoding.

      The current Java file encoding can be obtained from the "file.encoding" System property.

      Parameters:
      os - the stream to base the PrintStream on.
      autoFlush - whether or not to autoFlush
      encoding - the charset encoding to use
      enable - if false, transcoding is disabled
      Returns:
      the printStream
      Throws:
      UnsupportedEncodingException
      See Also:

    • getLoggingLevel

      public static int getLoggingLevel()
      Answer the current logging level for the Toolkit native code.
      See Also:

    • setLoggingLevel

      public static void setLoggingLevel(int level)
      Sets the logging level for the Toolkit native code. This method can be used to enable debugging output from the toolkit native library.

      In order of decreasing severity, the logging levels are:

      Alternatively, a system property can be used to set the toolkit logging level. This property has the form: -Djzos.logging={E|W|N|I|D|T}

      Parameters:
      level - one of the LOG_XXX constants. If an invalid level is given it is ignored, but a warning is logged.
      See Also:

    • getCodePageCurrentLocale

      public static String getCodePageCurrentLocale()
      Native method to retrieve the default locale codepage name used by the toolkit native library. This is the default codepage for the z/OS process based on the LANG environment variable.

    • getPid

      public static int getPid()
      Get the process id of the current process.

      This method calls the getpid() C-library routine.

      Returns:
      the process id.
      Since:
      2.1.0

    • getPPid

      public static int getPPid()
      Get the parent process id of the current process.

      This method calls the getppid() C-library routine.

      Returns:
      the parent process id.
      Since:
      2.1.0

    • getTodClock

      public static byte[] getTodClock()
      A JNI wrapper for the z/architecture STORE CLOCK (STCK) instruction

      Refer to SA22-7832 z/Architecture Principles of Operations for more information.

      Returns:
      byte[] an 8 byte array containing the TOD clock value
      Throws:
      RcException - if the STCK instruction returns a CC != 0 (should not happen)
      Since:
      2.3.0

    • getTodClock

      public static void getTodClock(byte[] buffer)
      A JNI wrapper for the z/architecture STORE CLOCK (STCK) instruction

      Refer to SA22-7832 z/Architecture Principles of Operations for more information.

      Parameters:
      buffer - a byte array a least 8 bytes long to receive the TOD clock value
      Throws:
      RcException - if the STCK instruction returns a CC != 0 (should not happen)
      IllegalArgumentException - if the given buffer is not at least 8 bytes in length
      Since:
      2.3.0

    • getTodClockExtended

      public static byte[] getTodClockExtended()
      A JNI wrapper for the z/architecture STORE CLOCK EXTENDED (STCKE) instruction

      Refer to SA22-7832 z/Architecture Principles of Operations for more information.

      Returns:
      byte[] a 16-byte byte array containing the extended TOD clock value
      Throws:
      RcException - if the STCKE instruction returns a CC != 0 (should not happen)
      Since:
      2.3.0

    • getTodClockExtended

      public static void getTodClockExtended(byte[] buffer)
      A JNI wrapper for the z/architecture STORE CLOCK EXTENDED (STCKE) instruction

      Refer to SA22-7832 z/Architecture Principles of Operations for more information.

      Parameters:
      buffer - a byte array a least 16 bytes long to receive the extended TOD clock value
      Throws:
      RcException - if the STCKE instruction returns a CC != 0 (should not happen)
      IllegalArgumentException - if the given buffer is not at least 16 bytes in length
      Since:
      2.3.0

    • smfRecord

      public static void smfRecord(int type, int subtype, byte[] record) throws ErrnoException
      Write a System Management Facility (SMF) record.

      This method calls the __smf_record() C-library routine. The first 24 bytes of the given record are reserved for the Standard SMF Record Header with Subtypes, as described in the manual: MVS Systems Management Facilities (SMF).

      Before writing the record, this API will overwrite the 24 byte SMF header area, filling in all header fields, including the current date/time and the system id (SID). If the SUBSYS starts with a blank or null(zero), then it is also filled in with either "JES2", "JES3", "TSO", or "STC" as appropriate. If the SUBSYS field starts with a character other than blank or null, then it is unchanged.

      Note: The "TZ" environment variable must be properly set to the correct timezone in order for the date/time in the SMF header to reflect the current local time.

      Throws:
      ErrnoException - on failure. Refer to __smf_record() API documentation for specific errno reason code constants, which are provided as constants in the ErrnoException class.

    • substituteSystemSymbols

      public static String substituteSystemSymbols(String pattern, boolean warn) throws RcException
      Substitute text for MVS system symbols.

      This method calls the ASASYMBM Assembler service. For more information, see MVS Programming: Assembler Services Reference, Volume 1 (SA22-7606). User symbol tables are not supported by this API.

      Parameters:
      pattern - a string containing MVS system symbol(s) to be substituted. MVS system symbols have the form &SYMBOL., or &SYMBOL(n:m). (if a substring of the resulting text is requested). In this case, n is the start index of the resulting text and m is the number of characters to substitute. For more information on how symbol substrings are specified, see the MVS Initialization and Tuning Reference (SA22-7592)
      warn - if true will force ASASYMBM to check for symbol substitution warnings. See the notes under RcException for details. If false, symbol substitution warnings are ignored.
      Returns:
      the pattern string with text substituted for the system symbols.
      Throws:
      RcException - if an error occurs with one of the following return codes:
      • 4 - warn=true and there was a substring error
      • 8 - the target buffer was too small to hold the substituted pattern
      • 12 - warn=true and the length of the text substituted for a system symbol was zero
      • 16 - warn=true and none of the specified symbols was substituted
      Since:
      2.3.0

    • substituteSystemSymbols

      public static String substituteSystemSymbols(String pattern) throws RcException
      Substitute text for MVS system symbols.

      Calls substituteSystemSymbols(String, boolean) with warn=false.

      Throws:
      RcException
      Since:
      2.3.0

    • touch

      public static void touch()

    • formatStackTrace

      public static String formatStackTrace(Throwable t)
      Print the stacktrace related to the supplied Throwable and return it as a String.