IV26985: JAVA.AWT.FONT.LINEBREAKMEASURER, TEXTMEASURER METHOD CALLS LEADS TO AN ENDLESS LOOP IN A MULTITHREADED APPLICATION

APAR status

• Closed as program error.

Error description

• Error Message: java.lang.NullPointerException in
  sun.font.GlyphLayout$EngineRecord.init result the hung.
  .
  Stack Trace:
  java/util/HashMap.findNonNullKeyEntry(HashMap.java:526(Compiled
  Code))
              java/util/HashMap.getEntry(HashMap.java(Compiled
  Code))
              java/util/HashMap.get(HashMap.java(Compiled Code))
  
  sun/font/SunLayoutEngine.getEngine(SunLayoutEngine.java:115(Comp
  iled Code))
  
  sun/font/GlyphLayout$EngineRecord.init(GlyphLayout.java:642(Comp
  iled Code))
  
  sun/font/GlyphLayout.nextEngineRecord(GlyphLayout.java:494(Compi
  led Code))
  
  sun/font/GlyphLayout.layout(GlyphLayout.java:417(Compiled Code))
  
  sun/font/ExtendedTextSourceLabel.createGV(ExtendedTextSourceLabe
  l.java:308(Compiled Code))
  
  sun/font/ExtendedTextSourceLabel.getGV(ExtendedTextSourceLabel.j
  ava:294(Compiled Code))
  
  sun/font/ExtendedTextSourceLabel.createCharinfo(ExtendedTextSour
  ceLabel.java:566(Compiled Code))
  
  sun/font/ExtendedTextSourceLabel.getCharinfo(ExtendedTextSourceL
  abel.java:492(Compiled Code))
  
  sun/font/ExtendedTextSourceLabel.getLineBreakIndex(ExtendedTextS
  ourceLabel.java:439(Compiled Code))
  
  java/awt/font/TextMeasurer.calcLineBreak(TextMeasurer.java:320(C
  ompiled Code))
  
  java/awt/font/TextMeasurer.getLineBreakIndex(TextMeasurer.java:5
  56)
  
  java/awt/font/LineBreakMeasurer.nextOffset(LineBreakMeasurer.jav
  a:352)
  
  java/awt/font/LineBreakMeasurer.nextLayout(LineBreakMeasurer.jav
  a:434)
  
  java/awt/font/LineBreakMeasurer.nextLayout(LineBreakMeasurer.jav
  a:407)
     ..
     ..
  .
  NA
  

Local fix

• NA
  

Problem summary

• java.awt.font.LineBreakMeasurer, TextMeasurer method calls leads
  to an endless loop in a multithreaded application. JDK internal
  implementation class (SunLayoutEngine) is not thread safe and
  also uses normal HashMap leading to an infinite loop and thus
  resulting hung.
  

Problem conclusion

• This defect will be fixed in:
  6.0.0 SR12
  6.0.1 SR4
  7.0.0 SR3
  .
  JVM has been updated to use concurrent HashMap to prevent the
  infinite loop in multithread enviornment.
  

Temporary fix

• NA
  

Comments

APAR Information

• APAR is sysrouted FROM one or more of the following:

• APAR is sysrouted TO one or more of the following:

Fix information

• Fixed component name

  JAVA CLASS LIBS

• Fixed component ID

  620700130

Applicable component levels

• R600 PSY

     UP

• R700 PSY

     UP