Topic
  • 2 replies
  • Latest Post - ‏2013-01-24T12:18:49Z by Ian_Partridge
Jon Samuel
Jon Samuel
9 Posts

Pinned topic IBM changes in the 1st drop (beta 1) of the Java 8 beta

‏2013-01-17T16:05:16Z |
§Removal of legacy and deprecated functionality
§JRIO on z/OS
Use JZOS record I/O instead
§Annotation Processing Tool (apt) and com.sun APIs
Use Pluggable Annotation Processing API instead (available since Java 6)
§
 
Limitations
§    Java plugin and Webstart unavailable
§    Kerberos security unavailable
§    Uninstallation leaves some files behind on Linux
 
§Enhancements to JVM dump API
§
§          Specify dump filename at runtime:
§                        com/ibm/jvm/Dump.javaDumpToFile(fileName)
                       
com/ibm/jvm/Dump.heapDumpToFile(fileName)
                       
com/ibm/jvm/Dump.systemDumpToFile(fileName)
                       
com/ibm/jvm/Dump.snapDumpToFile(fileName)
§
§         Setting and querying of dump options at runtime:
§                       com/ibm/jvm/Dump.setDumpOptions(options)
                      
com/ibm/jvm/Dump.queryDumpOptions()
                      
com/ibm/jvm/Dump.resetDumpOptions()
                       com
/ibm/jvm/Dump.triggerDump(options)
§New information available in javacore.txt files
§
§Hypervisor information:
2CISYSINFO     Hypervisor name = PowerVM
§Supported hypervisors:
KVM
VMWare
PowerVM
Hyper-V
z/VM
PR/SM
 
§Data Access Accelerator (DAA)
§A new Java API for bare-bones data conversion and arithmetic
§
§Operates directly on native data record (byte arrays)
No Java object tree created
§Orchestrated with JIT for deep platform optimization
§Avoid expensive Java object instantiation by allowing in-place operations
§Expose hardware acceleration in a platform and JVM-neutral manner
§Can provide significant speedup to record parsing frameworks
§Can provide significant speedup for data marshalling and inter-language communication
§Adding two Packed Decimal numbers in Java
No Packed Decimal type
Convert to Big Decimal -> Expensive!
 
Current Approach:
byte[] addPacked(array a[], array b[]) {
BigDecimal a_bd = convertPackedToBd(a[]);
BigDecimal b_bd = convertPackedToBd(b[]);
a_bd.add(b_bd);
return (convertBDtoPacked(a_bd));
 
Proposed Solution:
byte[] addPacked(array a[], array b[]) {
DAA.addPacked(a[], b[]);
return (a[]);
 
On Z, there are hardware packed instructions – i.e. AP (Add Packed)!
§Marshalling and Un-marshalling
Transform primitive type (short, int, long, float, double) byte array
Support both big/little-endian byte arrays
§Packed Decimal (PD) Operations
Arithmetic:  +, -, *, /, % on 2 PD operands
Relation:  >,<,>=,<=,==,!= on 2 PD operands
Error checking: checks if PD operand is well-formed
Other: shifting, and moving ops on PD operand
§Decimal Data Type Conversions
Decimal ↔ Primitive: Convert Packed Decimal(PD), External Decimal(ED), Unicode Decimal(UD) primitive types (int, long)
Decimal ↔ Decimal: Convert between different decimal types (PD,  ED, UD)
Decimal ↔ Java: Convert decimal types (PD, ED, UD) BigDecimal, BigInteger
 
 
Updated on 2013-01-24T12:18:49Z at 2013-01-24T12:18:49Z by Ian_Partridge
  • JohnMcNamara
    JohnMcNamara
    1 Post

    Re: IBM changes in the 1st drop (beta 1) of the Java 8 beta

    ‏2013-01-23T22:32:32Z  
     Thanks for this, will there be an os x version?
  • Ian_Partridge
    Ian_Partridge
    4 Posts

    Re: IBM changes in the 1st drop (beta 1) of the Java 8 beta

    ‏2013-01-24T12:18:49Z  
     Thanks for this, will there be an os x version?
     There will not be an Mac OS X version - IBM Java is not available on that platform.  Thanks.