AST and Compilation

abstract class ASTNode {
    /**
     * Gets the line number where this node appears in source.
     */
    int getLineNumber();
    
    /**
     * Gets the column number where this node appears in source.
     */
    int getColumnNumber();
    
    /**
     * Gets the last line number of this node.
     */
    int getLastLineNumber();
    
    /**
     * Gets the last column number of this node.
     */
    int getLastColumnNumber();
    
    /**
     * Gets the text representation of this node.
     */
    String getText();
    
    /**
     * Sets the source position for this node.
     */
    void setSourcePosition(ASTNode node);
    
    /**
     * Copies source position from another node.
     */
    void copyNodeMetaData(ASTNode other);
}

class ClassNode extends AnnotatedNode {
    /**
     * Creates a class node with the given name.
     */
    ClassNode(String name);
    
    /**
     * Creates a class node for the given class.
     */
    ClassNode(Class<?> clazz);
    
    /**
     * Gets the name of this class.
     */
    String getName();
    
    /**
     * Gets the unresolved name of this class.
     */
    String getUnresolvedName();
    
    /**
     * Gets all methods declared in this class.
     */
    List<MethodNode> getMethods();
    
    /**
     * Gets all fields declared in this class.
     */
    List<FieldNode> getFields();
    
    /**
     * Gets all properties declared in this class.
     */
    List<PropertyNode> getProperties();
    
    /**
     * Gets all constructors declared in this class.
     */
    List<ConstructorNode> getDeclaredConstructors();
    
    /**
     * Gets the superclass of this class.
     */
    ClassNode getSuperClass();
    
    /**
     * Sets the superclass of this class.
     */
    void setSuperClass(ClassNode superClass);
    
    /**
     * Gets the interfaces implemented by this class.
     */
    ClassNode[] getInterfaces();
    
    /**
     * Sets the interfaces implemented by this class.
     */
    void setInterfaces(ClassNode[] interfaces);
    
    /**
     * Gets the modifiers for this class.
     */
    int getModifiers();
    
    /**
     * Sets the modifiers for this class.
     */
    void setModifiers(int modifiers);
    
    /**
     * Checks if this class is an interface.
     */
    boolean isInterface();
    
    /**
     * Checks if this class is abstract.
     */
    boolean isAbstract();
    
    /**
     * Checks if this class is an enum.
     */
    boolean isEnum();
    
    /**
     * Checks if this class is an annotation.
     */
    boolean isAnnotationDefinition();
}

class MethodNode extends AnnotatedNode {
    /**
     * Creates a method node.
     */
    MethodNode(String name, int modifiers, ClassNode returnType, Parameter[] parameters, ClassNode[] exceptions, Statement code);
    
    /**
     * Gets the name of this method.
     */
    String getName();
    
    /**
     * Gets the modifiers for this method.
     */
    int getModifiers();
    
    /**
     * Sets the modifiers for this method.
     */
    void setModifiers(int modifiers);
    
    /**
     * Gets the return type of this method.
     */
    ClassNode getReturnType();
    
    /**
     * Sets the return type of this method.
     */
    void setReturnType(ClassNode returnType);
    
    /**
     * Gets the parameters of this method.
     */
    Parameter[] getParameters();
    
    /**
     * Sets the parameters of this method.
     */
    void setParameters(Parameter[] parameters);
    
    /**
     * Gets the exceptions thrown by this method.
     */
    ClassNode[] getExceptions();
    
    /**
     * Sets the exceptions thrown by this method.
     */
    void setExceptions(ClassNode[] exceptions);
    
    /**
     * Gets the code body of this method.
     */
    Statement getCode();
    
    /**
     * Sets the code body of this method.
     */
    void setCode(Statement code);
    
    /**
     * Checks if this method is abstract.
     */
    boolean isAbstract();
    
    /**
     * Checks if this method is static.
     */
    boolean isStatic();
    
    /**
     * Checks if this method is public.
     */
    boolean isPublic();
    
    /**
     * Checks if this method is private.
     */
    boolean isPrivate();
    
    /**
     * Checks if this method is protected.
     */
    boolean isProtected();
}

class FieldNode extends AnnotatedNode {
    /**
     * Creates a field node.
     */
    FieldNode(String name, int modifiers, ClassNode type, ClassNode declaringClass, Expression initialExpression);
    
    /**
     * Gets the name of this field.
     */
    String getName();
    
    /**
     * Gets the type of this field.
     */
    ClassNode getType();
    
    /**
     * Sets the type of this field.
     */
    void setType(ClassNode type);
    
    /**
     * Gets the modifiers for this field.
     */
    int getModifiers();
    
    /**
     * Sets the modifiers for this field.
     */
    void setModifiers(int modifiers);
    
    /**
     * Gets the initial expression for this field.
     */
    Expression getInitialExpression();
    
    /**
     * Sets the initial expression for this field.
     */
    void setInitialValueExpression(Expression initialValueExpression);
    
    /**
     * Gets the class that declares this field.
     */
    ClassNode getDeclaringClass();
    
    /**
     * Checks if this field is static.
     */
    boolean isStatic();
    
    /**
     * Checks if this field is final.
     */
    boolean isFinal();
    
    /**
     * Checks if this field is public.
     */
    boolean isPublic();
    
    /**
     * Checks if this field is private.
     */
    boolean isPrivate();
    
    /**
     * Checks if this field is protected.
     */
    boolean isProtected();
}

class PropertyNode extends AnnotatedNode {
    /**
     * Creates a property node.
     */
    PropertyNode(String name, int modifiers, ClassNode type, ClassNode declaringClass, Expression initialExpression, Statement getterBlock, Statement setterBlock);
    
    /**
     * Gets the name of this property.
     */
    String getName();
    
    /**
     * Gets the type of this property.
     */
    ClassNode getType();
    
    /**
     * Sets the type of this property.
     */
    void setType(ClassNode type);
    
    /**
     * Gets the modifiers for this property.
     */
    int getModifiers();
    
    /**
     * Gets the getter block for this property.
     */
    Statement getGetterBlock();
    
    /**
     * Sets the getter block for this property.
     */
    void setGetterBlock(Statement getterBlock);
    
    /**
     * Gets the setter block for this property.
     */
    Statement getSetterBlock();
    
    /**
     * Sets the setter block for this property.
     */
    void setSetterBlock(Statement setterBlock);
    
    /**
     * Gets the field associated with this property.
     */
    FieldNode getField();
    
    /**
     * Sets the field associated with this property.
     */
    void setField(FieldNode field);
}

class ModuleNode extends ASTNode {
    /**
     * Creates a module node.
     */
    ModuleNode(SourceUnit sourceUnit);
    
    /**
     * Gets all classes declared in this module.
     */
    List<ClassNode> getClasses();
    
    /**
     * Adds a class to this module.
     */
    void addClass(ClassNode node);
    
    /**
     * Gets the main class of this module.
     */
    ClassNode getScriptClassDummy();
    
    /**
     * Gets the statement block for script code.
     */
    BlockStatement getStatementBlock();
    
    /**
     * Sets the statement block for script code.
     */
    void setStatementBlock(BlockStatement statementBlock);
    
    /**
     * Gets all import statements.
     */
    List<ImportNode> getImports();
    
    /**
     * Adds an import statement.
     */
    void addImport(String alias, ClassNode type);
    
    /**
     * Gets all static import statements.
     */
    Map<String, ImportNode> getStaticImports();
    
    /**
     * Adds a static import statement.
     */
    void addStaticImport(ClassNode type, String fieldName, String alias);
    
    /**
     * Gets the package name.
     */
    String getPackageName();
    
    /**
     * Sets the package name.
     */
    void setPackageName(String packageName);
}

class PackageNode extends ASTNode {
    /**
     * Creates a package node.
     */
    PackageNode(String name);
    
    /**
     * Gets the package name.
     */
    String getName();
    
    /**
     * Gets the package name without the final dot.
     */
    String getPackageName();
}

class AstBuilder {
    /**
     * Creates an AST builder.
     */
    AstBuilder();
    
    /**
     * Builds AST from string source code.
     */
    List<ASTNode> buildFromString(String source);
    
    /**
     * Builds AST from string source with specified phase.
     */
    List<ASTNode> buildFromString(CompilePhase phase, String source);
    
    /**
     * Builds AST from string source with statementsOnly flag.
     */
    List<ASTNode> buildFromString(CompilePhase phase, boolean statementsOnly, String source);
    
    /**
     * Builds AST from closure code.
     */
    List<ASTNode> buildFromCode(Closure closure);
    
    /**
     * Builds AST from closure code with specified phase.
     */
    List<ASTNode> buildFromCode(CompilePhase phase, Closure closure);
    
    /**
     * Builds AST from closure code with statementsOnly flag.
     */
    List<ASTNode> buildFromCode(CompilePhase phase, boolean statementsOnly, Closure closure);
    
    /**
     * Builds AST from specification closure.
     */
    List<ASTNode> buildFromSpec(Closure specification);
}

class AnnotationNode extends ASTNode {
    /**
     * Creates an annotation node.
     */
    AnnotationNode(ClassNode type);
    
    /**
     * Gets the type of this annotation.
     */
    ClassNode getClassNode();
    
    /**
     * Gets all members of this annotation.
     */
    Map<String, Expression> getMembers();
    
    /**
     * Gets a specific member value.
     */
    Expression getMember(String name);
    
    /**
     * Sets a member value.
     */
    void setMember(String name, Expression value);
    
    /**
     * Adds a member value.
     */
    void addMember(String name, Expression value);
    
    /**
     * Checks if this annotation has a member with the given name.
     */
    boolean hasMember(String name);
    
    /**
     * Checks if this annotation has a runtime retention.
     */
    boolean hasRuntimeRetention();
    
    /**
     * Checks if this annotation has a source retention.
     */
    boolean hasSourceRetention();
    
    /**
     * Checks if this annotation has a class retention.
     */
    boolean hasClassRetention();
}

import org.codehaus.groovy.ast.*;
import org.codehaus.groovy.ast.builder.AstBuilder;

// Build AST from string
AstBuilder builder = new AstBuilder();
List<ASTNode> nodes = builder.buildFromString(
    "class HelloWorld { void sayHello() { println 'Hello!' } }"
);

ClassNode classNode = (ClassNode) nodes.get(0);
System.out.println("Class name: " + classNode.getName());

for (MethodNode method : classNode.getMethods()) {
    System.out.println("Method: " + method.getName());
}

import org.codehaus.groovy.transform.GroovyASTTransformation;
import org.codehaus.groovy.control.CompilePhase;
import org.codehaus.groovy.ast.ASTNode;
import org.codehaus.groovy.control.SourceUnit;

@GroovyASTTransformation(phase = CompilePhase.SEMANTIC_ANALYSIS)
public class MyASTTransformation implements ASTTransformation {
    
    public void visit(ASTNode[] nodes, SourceUnit source) {
        // Custom AST transformation logic
        for (ASTNode node : nodes) {
            if (node instanceof ClassNode) {
                ClassNode classNode = (ClassNode) node;
                // Modify the AST
                addToStringMethod(classNode);
            }
        }
    }
    
    private void addToStringMethod(ClassNode classNode) {
        // Add a toString method to the class
        // Implementation details...
    }
}

import org.codehaus.groovy.ast.*;
import org.codehaus.groovy.ast.stmt.*;
import org.codehaus.groovy.ast.expr.*;

// Create a new class programmatically
ClassNode classNode = new ClassNode("DynamicClass", 
    ClassNode.ACC_PUBLIC, ClassHelper.OBJECT_TYPE);

// Add a field
FieldNode field = new FieldNode("name", 
    ClassNode.ACC_PRIVATE, ClassHelper.STRING_TYPE, classNode, 
    new ConstantExpression("default"));
classNode.addField(field);

// Add a getter method
MethodNode getter = new MethodNode("getName", 
    ClassNode.ACC_PUBLIC, ClassHelper.STRING_TYPE, 
    Parameter.EMPTY_ARRAY, ClassNode.EMPTY_ARRAY,
    new ReturnStatement(new FieldExpression(field)));
classNode.addMethod(getter);

// Compile and use the class
GroovyClassLoader loader = new GroovyClassLoader();
Class<?> dynamicClass = loader.defineClass(classNode);
Object instance = dynamicClass.newInstance();