Java Token.EXPR_VOID属性代码示例

/**
 * compile the expression from a script tree
 * 
 * @param expression
 * @param context
 * @param tree
 * @param columnExprList
 * @throws BirtException
 */
private void CompiledExprFromTree( String expression, Context context,
		ScriptNode tree, List columnExprList ) throws BirtException
{
	if ( tree.getFirstChild( ) == tree.getLastChild( ) )
	{
		if ( tree.getFirstChild( ).getType( ) == Token.FUNCTION )
		{
			int index = getFunctionIndex( tree.getFirstChild( ).getString( ),
					tree );
			compileFunctionNode( tree.getFunctionNode( index ),
					tree,
					columnExprList );
		}
		else
		{
			// A single expression
			if ( tree.getFirstChild( ).getType( ) != Token.EXPR_RESULT
					&& tree.getFirstChild( ).getType( ) != Token.EXPR_VOID
					&& tree.getFirstChild( ).getType( ) != Token.BLOCK
					&& tree.getFirstChild( ).getType( ) != Token.SCRIPT)
			{
				// This should never happen?
				throw new CoreException( pluginId,
						ResourceConstants.INVALID_EXPRESSION );
			}
			Node exprNode = tree.getFirstChild( );
			processChild( exprNode, tree, columnExprList );
		}
	}
	else
	{
		compileComplexExpr( tree, tree, columnExprList );
	}
}
 

/**
 * process the script tree to produce a <code>CompiledExpression</code>
 * 
 * @param expression
 * @param tree
 * @param context
 * @return @throws
 *         DataException
 */
private CompiledExpression processScriptTree( String expression,
		ScriptNode tree, Context context ) throws DataException

{
	CompiledExpression expr;
	if ( tree.getFirstChild( ) == tree.getLastChild( ) )
	{
		if( tree.getFirstChild( ) == null )
			throw new DataException( "Expression parse error: first child is null. The expression is " + expression,
					expression );
		// A single expression
		if ( tree.getFirstChild( ).getType( ) != Token.EXPR_RESULT
				&& tree.getFirstChild( ).getType( ) != Token.EXPR_VOID
				&& tree.getFirstChild( ).getType( ) != Token.BLOCK )
		{
			// This should never happen?
			throw new DataException( ResourceConstants.INVALID_JS_EXPR,
					expression );
		}
		Node child, parent = tree;
		Node exprNode = parent.getFirstChild( );
		child = exprNode.getFirstChild( );
		if ( child.getNext( ) != null )
			child = exprNode;
		else
		{
			parent = exprNode;
		}
		assert ( child != null && parent != null );
		expr = processChild( context, false, parent, child, tree );
	}
	else
	{
		// complex expressions
		// Multiple expressions exist; we should produce complex expressions
		// However, individual subexpressions still needs to be processed
		// to identify the interesting subexpressions
		expr = compileComplexExpr( context, tree, false );
	}
	if ( expr instanceof BytecodeExpression )
		compileForBytecodeExpr( context, tree, expr );
	return expr;
}
 

/**
 * whether the expression is column reference
 * @param expression
 * @return
 */
public static boolean isColumnExpression( String expression, boolean mode )
{
	boolean isColumn = false;
	if ( expression == null || expression.trim( ).length( ) == 0 )
		return isColumn;
	if ( getCompiledExpCacheMap( mode ).containsKey( expression ) )
	{
		return ( (Boolean)  getCompiledExpCacheMap( mode ).get( expression ) ).booleanValue( );
	}
	Context context = Context.enter( );
	ScriptNode tree;
	try
	{
		CompilerEnvirons m_compilerEnv = new CompilerEnvirons( );
		m_compilerEnv.initFromContext( context );
		Parser p = new Parser( m_compilerEnv, context.getErrorReporter( ) );
		AstRoot root = p.parse( expression, null, 0 );
		IRFactory ir = new IRFactory( m_compilerEnv );
		tree = ir.transformTree( root );
	}
	catch ( Exception e )
	{
		getCompiledExpCacheMap( mode ).put( expression,
				Boolean.valueOf( false ) );
		return false;
	}
	finally
	{
		Context.exit( );
	}

	if ( tree.getFirstChild( ) == tree.getLastChild( ) )
	{
		// A single expression
		if ( tree.getFirstChild( ).getType( ) != Token.EXPR_RESULT
				&& tree.getFirstChild( ).getType( ) != Token.EXPR_VOID
				&& tree.getFirstChild( ).getType( ) != Token.BLOCK )
		{
			isColumn = false;
		}
		Node exprNode = tree.getFirstChild( );
		Node child = exprNode.getFirstChild( );
		assert ( child != null );
		if ( child.getType( ) == Token.GETELEM
				|| child.getType( ) == Token.GETPROP )
			isColumn = getDirectColRefExpr( child, mode );
		else
			isColumn = false;
	}
	else
	{
		isColumn = false;
	}
	getCompiledExpCacheMap( mode ).put( expression,
			Boolean.valueOf( isColumn ) );
	return isColumn;
}
 

/**
 * whether the expression is column reference
 * 
 * @param expression
 * @return
 */
public static boolean isColumnExpression( String expression )
{
	boolean isColumn = false;
	if ( expression == null || expression.trim( ).length( ) == 0 )
		return isColumn;
	if ( compiledExprCache.containsKey( expression ) )
		return ( (Boolean) compiledExprCache.get( expression ) ).booleanValue( );
	Context context = Context.enter( );
	ScriptNode tree;
	try
	{
		CompilerEnvirons m_compilerEnv = new CompilerEnvirons( );
		m_compilerEnv.initFromContext( context );
		Parser p = new Parser( m_compilerEnv, context.getErrorReporter( ) );
		AstRoot root = p.parse( expression, null, 0 );
		IRFactory ir = new IRFactory( m_compilerEnv );
		tree = ir.transformTree( root );
	}
	catch ( Exception e )
	{
		compiledExprCache.put( expression, Boolean.valueOf( false ) );
		return false;
	}
	finally
	{
		Context.exit( );
	}

	if ( tree.getFirstChild( ) == tree.getLastChild( ) )
	{
		// A single expression
		if ( tree.getFirstChild( ).getType( ) != Token.EXPR_RESULT
				&& tree.getFirstChild( ).getType( ) != Token.EXPR_VOID
				&& tree.getFirstChild( ).getType( ) != Token.BLOCK )
		{
			isColumn = false;
		}
		Node exprNode = tree.getFirstChild( );
		Node child = exprNode.getFirstChild( );
		assert ( child != null );
		if ( child.getType( ) == Token.GETELEM
				|| child.getType( ) == Token.GETPROP )
			isColumn = getDirectColRefExpr( child );
		else
			isColumn = false;
	}
	else
	{
		isColumn = false;
	}

	compiledExprCache.put( expression, Boolean.valueOf( isColumn ) );
	return isColumn;
}