Fujitsu V6.0 manual

Notes on JDK/JRE

Notes on JDK/JRE

Notes on Java VM

The default JavaVM when using JDK/JRE1.3.1_06 and 1.4.1_01 in Interstage Java Server Package is Fujitsu JavaVM (FJVM). This default is synonymous with specifying "-fjvm" in the java command option.

Notes on OutOfMemoryError Caused by a Permanent Area Shortage

The Permanent area is one of heap areas used to manage objects (Java classes and methods) that are permanently referenced by HostSpotVM (including FJVM), which is a JavaVM introduced to JDK/JRE

1.3and later. For a Java application that uses many classes and methods, the size of the Permanent area must be increased. Especially if an OutOfMemroyError occurs irrespective of how much the maximum heap value (specified in -Xmx) is increased, a Permanent area shortage may be one of the possible causes. The default size of the Permanent area is as follows:

•JDK1.3.1(HotSpot ClientVM): 32MB

•JDK1.3.1(FJVM, HotSpot ServerVM): 64MB

•JDK1.4.1(HotSpot ClientVM): 64MB

•JDK1.4.1(FJVM, HotSpot ServerVM): 64MB

The size of the Permanent area can be specified using JavaVM option "-XX:MaxPermSize." Example: Set the maximum size of the Permanent area to 128 MB: -XX:MaxPermSize=128m

Notes on java.lang.Object.wait()

After JDK/JRE is installed, java.lang.Object.wait() may be released (spurious wakeups) without waiting for a restart instruction (notification), interruption, or time-out. Therefore, make a program so that wait() is used in a loop.

Reference: Notes on the return value of java.beans.PropertyDescriptor.getWriteMethod()

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