package com.mindprod.common11;
import java.awt.Color;
import java.awt.Container;
import java.awt.TextArea;
/**
* VersionCheck.java Check that Java version is sufficiently recent
copyright
* (c) 1997-2005 Roedy Green, Canadian Mind Products #327 - 964
Heywood Avenue
* Victoria, BC Canada V8V 2Y5 mailto:
[email protected]
http://mindprod.com
*
* @version 1.5 2005-07-14 split off from Misc, allow for compilation
with old
* compiler. version 1.4 2002 August 17, add quoteSQL version
1.3 1999
* August 24, add leftPad, rightPad, smarter rep.
isJavaVersionOK now
* handles 1.3beta. version 1.2 1998 December 14, add
isJavaVersionOK
* version 1.1 1998 November 10, add dates version 1.0 1997
March 23,
* initial.
*/
public class VersionCheck {
/**
* true if you want extra debugging output and test code
*/
static final boolean DEBUGGING = false;
/**
* VersionCheck contains only static methods.
*/
private VersionCheck()
{
}
/**
* Ensures Java runtime version e.g. 1.1.7 is sufficiently recent.
Based on
* code by Dr. Tony Dahlman <
[email protected]>
*
* @param wantedMajor
* java major version e.g. 1
* @param wantedMinor
* Java minor version e.g. 1
* @param wantedBugFix
* Java bugfix version e.g. 7
* @return true if JVM version running is equal to or more recent
than
* (higher than) the level specified.
*/
public static boolean isJavaVersionOK ( int wantedMajor, int
wantedMinor,
int wantedBugFix )
{
try
{
try
{
// java.version will have form 1.1.7A, 11, 1.1., 1.1,
1.3beta,
// 1.4.2_05 or 1.4.1-rc
// It may be gibberish. It may be undefined.
// We have do deal with all this malformed garbage.
// Because incompetents run the world,
// it is not nicely formatted for us in three fields.
String ver = System.getProperty( "java.version" );
if ( ver == null ) { return false; }
ver = ver.trim();
if ( ver.length() < 2 ) { return false; }
int dex = ver.indexOf( '.' );
if ( dex < 0 )
{
// provide missing dot
ver = ver.charAt( 0 ) + '.' + ver.substring( 1 );
dex = 1;
}
int gotMajor = Integer.parseInt( ver.substring( 0, dex
) );
if ( DEBUGGING )
{
System.out.println( "major:" + gotMajor );
}
if ( gotMajor < wantedMajor ) return false;
if ( gotMajor > wantedMajor ) return true;
// chop off major and first dot.
ver = ver.substring( dex + 1 );
// chop trailing "beta"
if ( ver.endsWith( "beta" ) )
{
ver = ver.substring( 0, ver.length() -
"beta".length() );
}
// chop trailing "-rc"
if ( ver.endsWith( "-rc" ) )
{
ver = ver.substring( 0, ver.length() -
"-rc".length() );
}
// chop any trailing _nn
dex = ver.lastIndexOf( '_' );
if ( dex >= 0 )
{
ver = ver.substring( 0, dex );
}
// chop any trailing letter as in 1.1.7A,
// but convert 1.1.x or 1.1.X to 1.1.9
char ch = ver.charAt( ver.length() - 1 );
if ( !Character.isDigit( ch ) )
{
ver = ver.substring( 0, ver.length() - 1 );
if ( ch == 'x' || ch == 'X' ) ver += '9';
}
// check minor version
dex = ver.indexOf( '.' );
if ( dex < 0 )
{
// provide missing BugFix number as in 1.2 or 1.0
ver += ".0";
dex = ver.indexOf( '.' );
}
int gotMinor = Integer.parseInt( ver.substring( 0, dex
) );
if ( DEBUGGING )
{
System.out.println( "minor:" + gotMinor );
}
if ( gotMinor < wantedMinor ) return false;
if ( gotMinor > wantedMinor ) return true;
// was equal, need to examine third field.
// check bugfix version
ver = ver.substring( dex + 1 );
int gotBugFix = Integer.parseInt( ver );
if ( DEBUGGING )
{
System.out.println( "bugFix:" + gotBugFix );
}
return ( gotBugFix >= wantedBugFix );
}
catch ( NumberFormatException e )
{
if ( DEBUGGING )
{
System.out.println( "number format" +
e.getMessage() );
}
return false;
} // end catch
}
catch ( StringIndexOutOfBoundsException e )
{
if ( DEBUGGING )
{
System.out.println( "out of bounds:" + e.getMessage()
);
}
return false;
} // end catch
} // end isJavaVersionOK
/**
* use in a paint routine if Java version is not ok, usually
tested
* statically.
*
* @param wantedMajor
* java major version e.g. 1
* @param wantedMinor
* Java minor version e.g. 1
* @param wantedBugFix
* Java bugfix version e.g. 7
* @param container
* container to add an error message component.
* @return true if version is ok
*/
public static boolean isJavaVersionOK ( int wantedMajor, int
wantedMinor,
int wantedBugFix, Container container )
{
if ( isJavaVersionOK( wantedMajor, wantedMinor, wantedBugFix )
)
{
return true;
}
else
{
String error = "Error: You need Java "
+ wantedMajor
+ "."
+ wantedMinor
+ "."
+ wantedBugFix
+ " or later to run this Applet.\n"
+ "You are currently running under Java "
+ System.getProperty( "java.version" )
+ ".\n"
+ "Get the latest Java from
http://java.com/en/index.jsp";
TextArea complain = new TextArea( error, 3, 42,
TextArea.SCROLLBARS_NONE );
complain.setEditable( false );
complain.setBackground( Color.white );
complain.setForeground( Color.red );
complain.setSize( 300, 50 );
container.setLayout( null );
container.add( complain );
System.err.println( error );
return false;
}
}
} // end class VersionCheck
lugin> which will a) prompt the user to install