org.apache.derby.iapi.services.info
Class JVMInfo

java.lang.Object
  org.apache.derby.iapi.services.info.JVMInfo

public abstract class JVMInfo
extends java.lang.Object

This class is used to determine which Java specification Derby will run at. For a useful discussion of how this class is used, please see DERBY-3176.

Field Summary

static boolean	J2ME
static int	J2SE_14
static int	J2SE_142
static int	J2SE_15
static int	J2SE_16
static int	J2SE_17
static int	J2SE_18
static int	JDK_ID The JVM's runtime environment.

Constructor Summary

JVMInfo()

Method Summary

static java.lang.String	derbyVMLevel() Return Derby's understanding of the virtual machine's environment.
private static java.lang.String	getSystemProperty(java.lang.String name) Get system property.
static boolean	hasJNDI() Determine whether we are running in a constrained environment.
static boolean	isIBMJVM() Check whether this is IBM jvm.
static boolean	isSunJVM() Check whether this is sun jvm.
static void	javaDump() For IBM jvm, this method will dump more diagnostic information to file.
private static boolean	vmCheck(java.lang.String vmVersion, java.lang.String id) Check the vmVersion against a speciifc value.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

JDK_ID

public static final int JDK_ID

The JVM's runtime environment.

• 1 - not used was JDK 1.1
• 2 - not used, was for JDK 1.2 and 1.3
• 4 - J2SE_14 - JDK 1.4.0 or 1.4.1
• 5 - J2SE_142 - JDK 1.4.2
• 6 - J2SE_15 - JDK 1.5
• 7 - J2SE_16 - JDK 1.6
• 8 - J2SE_17 - JDK 1.7
• 9 - J2SE_18 - JDK 1.8

J2SE_14

public static final int J2SE_14

See Also:

Constant Field Values

J2SE_142

public static final int J2SE_142

See Also:

Constant Field Values

J2SE_15

public static final int J2SE_15

See Also:

Constant Field Values

J2SE_16

public static final int J2SE_16

See Also:

Constant Field Values

J2SE_17

public static final int J2SE_17

See Also:

Constant Field Values

J2SE_18

public static final int J2SE_18

See Also:

Constant Field Values

J2ME

public static final boolean J2ME

Constructor Detail

JVMInfo

public JVMInfo()

Method Detail

vmCheck

private static boolean vmCheck(java.lang.String vmVersion,
                               java.lang.String id)

Check the vmVersion against a speciifc value. Sun jvms are of the form

derbyVMLevel

public static java.lang.String derbyVMLevel()

Return Derby's understanding of the virtual machine's environment.

getSystemProperty

private static java.lang.String getSystemProperty(java.lang.String name)

Get system property.

Parameters:

name - name of the property

isSunJVM

public static final boolean isSunJVM()

Check whether this is sun jvm.

Returns:

true if it is sun jvm, false if it is not sun jvm

isIBMJVM

public static final boolean isIBMJVM()

Check whether this is IBM jvm.

Returns:

true if it is IBM jvm, false if it is not IBM jvm

javaDump

public static void javaDump()

For IBM jvm, this method will dump more diagnostic information to file. JVM specific code for other vender can be added. DERBY-4856

hasJNDI

public static boolean hasJNDI()

Determine whether we are running in a constrained environment.

Returns:

true if JNDI is available