in maven-core/src/main/java/org/apache/maven/plugin/PluginParameterExpressionEvaluator.java [130:357]
public Object evaluate( String expr )
throws ExpressionEvaluationException
{
Object value = null;
if ( expr == null )
{
return null;
}
String expression = stripTokens( expr );
if ( expression.equals( expr ) )
{
int index = expr.indexOf( "${" );
if ( index >= 0 )
{
int lastIndex = expr.indexOf( "}", index );
if ( lastIndex >= 0 )
{
String retVal = expr.substring( 0, index );
if ( index > 0 && expr.charAt( index - 1 ) == '$' )
{
retVal += expr.substring( index + 1, lastIndex + 1 );
}
else
{
retVal += evaluate( expr.substring( index, lastIndex + 1 ) );
}
retVal += evaluate( expr.substring( lastIndex + 1 ) );
return retVal;
}
}
// Was not an expression
if ( expression.indexOf( "$$" ) > -1 )
{
return expression.replaceAll( "\\$\\$", "\\$" );
}
else
{
return expression;
}
}
MojoDescriptor mojoDescriptor = mojoExecution.getMojoDescriptor();
if ( BANNED_EXPRESSIONS.containsKey( expression ) )
{
throw new ExpressionEvaluationException( "The parameter expression: \'" + expression
+ "\' used in mojo: \'" + mojoDescriptor.getGoal() + "\' is banned. Use \'"
+ BANNED_EXPRESSIONS.get( expression ) + "\' instead." );
}
else if ( DEPRECATED_EXPRESSIONS.containsKey( expression ) )
{
logger.warn( "The parameter expression: \'" + expression + "\' used in mojo: \'"
+ mojoDescriptor.getGoal() + "\' has been deprecated. Use \'" + DEPRECATED_EXPRESSIONS.get( expression )
+ "\' instead." );
}
if ( "localRepository".equals( expression ) )
{
value = context.getLocalRepository();
}
else if ( "session".equals( expression ) )
{
value = context;
}
else if ( "reactorProjects".equals( expression ) )
{
value = context.getSortedProjects();
}
else if ( "reports".equals( expression ) )
{
value = mojoExecution.getReports();
}
else if ( "mojoExecution".equals( expression ) )
{
value = mojoExecution;
}
else if ( "project".equals( expression ) )
{
value = project;
}
else if ( "executedProject".equals( expression ) )
{
value = project.getExecutionProject();
}
else if ( expression.startsWith( "project" ) )
{
try
{
int pathSeparator = expression.indexOf( "/" );
if ( pathSeparator > 0 )
{
String pathExpression = expression.substring( 0, pathSeparator );
value = ReflectionValueExtractor.evaluate( pathExpression, project );
value = value + expression.substring( pathSeparator );
}
else
{
value = ReflectionValueExtractor.evaluate( expression.substring( 1 ), project );
}
}
catch ( Exception e )
{
// TODO: don't catch exception
throw new ExpressionEvaluationException( "Error evaluating plugin parameter expression: " + expression,
e );
}
}
else if ( expression.startsWith( "plugin" ) )
{
try
{
int pathSeparator = expression.indexOf( "/" );
PluginDescriptor pluginDescriptor = mojoDescriptor.getPluginDescriptor();
if ( pathSeparator > 0 )
{
String pathExpression = expression.substring( 1, pathSeparator );
value = ReflectionValueExtractor.evaluate( pathExpression, pluginDescriptor );
value = value + expression.substring( pathSeparator );
}
else
{
value = ReflectionValueExtractor.evaluate( expression.substring( 1 ), pluginDescriptor );
}
}
catch ( Exception e )
{
// TODO: don't catch exception
throw new ExpressionEvaluationException( "Error evaluating plugin parameter expression: " + expression,
e );
}
}
else if ( "settings".equals( expression ) )
{
value = context.getSettings();
}
else if ( expression.startsWith( "settings" ) )
{
try
{
int pathSeparator = expression.indexOf( "/" );
if ( pathSeparator > 0 )
{
String pathExpression = expression.substring( 1, pathSeparator );
value = ReflectionValueExtractor.evaluate( pathExpression, context.getSettings() );
value = value + expression.substring( pathSeparator );
}
else
{
value = ReflectionValueExtractor.evaluate( expression.substring( 1 ), context.getSettings() );
}
}
catch ( Exception e )
{
// TODO: don't catch exception
throw new ExpressionEvaluationException( "Error evaluating plugin parameter expression: " + expression,
e );
}
}
else if ( "basedir".equals( expression ) )
{
value = basedir;
}
else if ( expression.startsWith( "basedir" ) )
{
int pathSeparator = expression.indexOf( "/" );
if ( pathSeparator > 0 )
{
value = basedir + expression.substring( pathSeparator );
}
else
{
logger.error( "Got expression '" + expression + "' that was not recognised" );
}
}
if ( value == null )
{
// The CLI should win for defining properties
if ( value == null && properties != null )
{
// We will attempt to get nab a system property as a way to specify a
// parameter to a plugins. My particular case here is allowing the surefire
// plugin to run a single test so I want to specify that class on the cli
// as a parameter.
value = properties.getProperty( expression );
}
if ( value == null && project != null && project.getProperties() != null )
{
value = project.getProperties().getProperty( expression );
}
}
if ( value instanceof String )
{
// TODO: without #, this could just be an evaluate call...
String val = (String) value;
int exprStartDelimiter = val.indexOf( "${" );
if ( exprStartDelimiter >= 0 )
{
if ( exprStartDelimiter > 0 )
{
value = val.substring( 0, exprStartDelimiter ) + evaluate( val.substring( exprStartDelimiter ) );
}
else
{
value = evaluate( val.substring( exprStartDelimiter ) );
}
}
}
return value;
}