Package org.codehaus.groovy.ast

Class MethodInvocationTrap

java.lang.Object
org.codehaus.groovy.ast.CodeVisitorSupport
org.codehaus.groovy.ast.MethodInvocationTrap
All Implemented Interfaces:
GroovyCodeVisitor
public abstract class MethodInvocationTrap extends CodeVisitorSupport
Abstract base class for AST visitors that trap and intercept specific method invocations. Primarily used to detect AstBuilder "from code" invocations and convert them to the equivalent "from string" approach during compilation.

Subclasses implement isBuildInvocation() to identify target method calls and handleTargetMethodCallExpression() to transform them. The base class provides utility methods for error reporting and closure-to-source conversion.

See Also:

  • Field Details

    • source

      protected final ReaderSource source
      The source reader for extracting closure source code.

    • sourceUnit

      protected final SourceUnit sourceUnit
      The source unit for reporting errors and accessing compilation context.

  • Constructor Details

    • MethodInvocationTrap

      public MethodInvocationTrap(ReaderSource source, SourceUnit sourceUnit)
      Creates a method invocation trap with the given source and source unit. Both arguments are required; null values will raise IllegalArgumentException.
      Parameters:
      source - the ReaderSource for extracting source code from closures, cannot be null
      sourceUnit - the SourceUnit for error reporting, cannot be null
      Throws:
      IllegalArgumentException - if either parameter is null

  • Method Details

    • visitMethodCallExpression

      public void visitMethodCallExpression(MethodCallExpression call)
      Visits a method call expression, checking if it is a target build invocation. If identified as a target invocation, calls handleTargetMethodCallExpression(). If that method returns true, resumes normal tree walking; otherwise stops. For non-target method calls, continues normal tree walking regardless.
      Specified by:
      visitMethodCallExpression in interface GroovyCodeVisitor
      Overrides:
      visitMethodCallExpression in class CodeVisitorSupport
      Parameters:
      call - the method call expression that may or may not be an AstBuilder 'from code' invocation

    • addError

      protected void addError(String msg, ASTNode expr)
      Reports an error back to the source unit with line and column information. The error is collected and processing continues.
      Parameters:
      msg - the error message
      expr - the expression that caused the error

    • convertClosureToSource

      protected String convertClosureToSource(ClosureExpression expression)
      Converts a closure expression into its source code equivalent using the source reader. If an error occurs during conversion, adds an error to the source unit and returns null.
      Parameters:
      expression - the closure expression to convert
      Returns:
      the source code string of the closure, or null if conversion fails

    • isBuildInvocation

      protected abstract boolean isBuildInvocation(MethodCallExpression call)
      Determines whether a method call expression is a target invocation for special handling. Subclasses override to identify invocations matching their specific criteria.
      Parameters:
      call - the method call expression to check
      Returns:
      true if this call is a target invocation requiring special handling

    • handleTargetMethodCallExpression

      protected abstract boolean handleTargetMethodCallExpression(MethodCallExpression call)
      Handles a target method call expression by transforming or validating it. Subclasses override to implement the transformation logic.
      Parameters:
      call - the target method call expression
      Returns:
      true to continue tree walking, false to stop