Bug 145022 Provide a utility method to help GUI enhance aggregate on.
DtE will provide a method hasAggregation(String expression) in org.eclipse.birt.core.data.ExpressionUtil, and the return value will be true when the expression is a valid JS expression and it has aggregation defined.
core/org.eclipse.birt.core/src/org/eclipse/birt/core/data/ExpressionUtil.java
private String columnName;
	private String expression;
	private int level;
	ColumnBinding( String columnName, String expression )
	{
		this.columnName = columnName;
		this.expression = expression;
		this.level = 0;
	}
	
	ColumnBinding( String columnName, String expression, int level )
	{
		this.columnName = columnName;
		this.expression = expression;
		this.level = level;
	}
	
	public String getResultSetColumnName( )
	{
		return this.columnName;
	}
	public String getBoundExpression( )
	{
		return this.expression;
	}
	public int getOuterLevel( )
	{
		return level;
	}
}