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package com.sun.source.util;

import java.lang.reflect.Method;

import javax.annotation.processing.ProcessingEnvironment;
import javax.lang.model.element.AnnotationMirror;
import javax.lang.model.element.AnnotationValue;
import javax.lang.model.element.Element;
import javax.lang.model.element.ExecutableElement;
import javax.lang.model.element.TypeElement;
import javax.lang.model.type.DeclaredType;
import javax.lang.model.type.ErrorType;
import javax.lang.model.type.TypeMirror;
import javax.tools.Diagnostic;
import javax.tools.JavaCompiler.CompilationTask;

import com.sun.source.tree.CatchTree;
import com.sun.source.tree.ClassTree;
import com.sun.source.tree.CompilationUnitTree;
import com.sun.source.tree.MethodTree;
import com.sun.source.tree.Scope;
import com.sun.source.tree.Tree;

Bridges JSR 199, JSR 269, and the Tree API.
Author:Peter von der Ahé
/** * Bridges JSR 199, JSR 269, and the Tree API. * * @author Peter von der Ahé */
public abstract class Trees {
Constructor for subclasses to call.
/** * Constructor for subclasses to call. */
public Trees() {}
Returns a Trees object for a given CompilationTask.
Params:
  • task – the compilation task for which to get the Trees object
Throws:
Returns:the Trees object
/** * Returns a Trees object for a given CompilationTask. * @param task the compilation task for which to get the Trees object * @throws IllegalArgumentException if the task does not support the Trees API. * @return the Trees object */
public static Trees instance(CompilationTask task) { String taskClassName = task.getClass().getName(); if (!taskClassName.equals("com.sun.tools.javac.api.JavacTaskImpl") && !taskClassName.equals("com.sun.tools.javac.api.BasicJavacTask")) throw new IllegalArgumentException(); return getJavacTrees(CompilationTask.class, task); }
Returns a Trees object for a given ProcessingEnvironment.
Params:
  • env – the processing environment for which to get the Trees object
Throws:
Returns:the Trees object
/** * Returns a Trees object for a given ProcessingEnvironment. * @param env the processing environment for which to get the Trees object * @throws IllegalArgumentException if the env does not support the Trees API. * @return the Trees object */
public static Trees instance(ProcessingEnvironment env) { if (!env.getClass().getName().equals("com.sun.tools.javac.processing.JavacProcessingEnvironment")) throw new IllegalArgumentException(); return getJavacTrees(ProcessingEnvironment.class, env); } static Trees getJavacTrees(Class<?> argType, Object arg) { try { ClassLoader cl = arg.getClass().getClassLoader(); Class<?> c = Class.forName("com.sun.tools.javac.api.JavacTrees", false, cl); argType = Class.forName(argType.getName(), false, cl); Method m = c.getMethod("instance", argType); return (Trees) m.invoke(null, arg); } catch (ReflectiveOperationException e) { throw new AssertionError(e); } }
Returns a utility object for obtaining source positions.
Returns:the utility object for obtaining source positions
/** * Returns a utility object for obtaining source positions. * @return the utility object for obtaining source positions */
public abstract SourcePositions getSourcePositions();
Returns the Tree node for a given Element. Returns null if the node can not be found.
Params:
  • element – the element
Returns:the tree node
/** * Returns the Tree node for a given Element. * Returns {@code null} if the node can not be found. * @param element the element * @return the tree node */
public abstract Tree getTree(Element element);
Returns the ClassTree node for a given TypeElement. Returns null if the node can not be found.
Params:
  • element – the element
Returns:the class tree node
/** * Returns the ClassTree node for a given TypeElement. * Returns {@code null} if the node can not be found. * @param element the element * @return the class tree node */
public abstract ClassTree getTree(TypeElement element);
Returns the MethodTree node for a given ExecutableElement. Returns null if the node can not be found.
Params:
  • method – the executable element
Returns:the method tree node
/** * Returns the MethodTree node for a given ExecutableElement. * Returns {@code null} if the node can not be found. * @param method the executable element * @return the method tree node */
public abstract MethodTree getTree(ExecutableElement method);
Returns the Tree node for an AnnotationMirror on a given Element. Returns null if the node can not be found.
Params:
  • e – the element
  • a – the annotation mirror
Returns:the tree node
/** * Returns the Tree node for an AnnotationMirror on a given Element. * Returns {@code null} if the node can not be found. * @param e the element * @param a the annotation mirror * @return the tree node */
public abstract Tree getTree(Element e, AnnotationMirror a);
Returns the Tree node for an AnnotationValue for an AnnotationMirror on a given Element. Returns null if the node can not be found.
Params:
  • e – the element
  • a – the annotation mirror
  • v – the annotation value
Returns:the tree node
/** * Returns the Tree node for an AnnotationValue for an AnnotationMirror on a given Element. * Returns {@code null} if the node can not be found. * @param e the element * @param a the annotation mirror * @param v the annotation value * @return the tree node */
public abstract Tree getTree(Element e, AnnotationMirror a, AnnotationValue v);
Returns the path to tree node within the specified compilation unit.
Params:
  • unit – the compilation unit
  • node – the tree node
Returns:the tree path
/** * Returns the path to tree node within the specified compilation unit. * @param unit the compilation unit * @param node the tree node * @return the tree path */
public abstract TreePath getPath(CompilationUnitTree unit, Tree node);
Returns the TreePath node for a given Element. Returns null if the node can not be found.
Params:
  • e – the element
Returns:the tree path
/** * Returns the TreePath node for a given Element. * Returns {@code null} if the node can not be found. * @param e the element * @return the tree path */
public abstract TreePath getPath(Element e);
Returns the TreePath node for an AnnotationMirror on a given Element. Returns null if the node can not be found.
Params:
  • e – the element
  • a – the annotation mirror
Returns:the tree path
/** * Returns the TreePath node for an AnnotationMirror on a given Element. * Returns {@code null} if the node can not be found. * @param e the element * @param a the annotation mirror * @return the tree path */
public abstract TreePath getPath(Element e, AnnotationMirror a);
Returns the TreePath node for an AnnotationValue for an AnnotationMirror on a given Element. Returns null if the node can not be found.
Params:
  • e – the element
  • a – the annotation mirror
  • v – the annotation value
Returns:the tree path
/** * Returns the TreePath node for an AnnotationValue for an AnnotationMirror on a given Element. * Returns {@code null} if the node can not be found. * @param e the element * @param a the annotation mirror * @param v the annotation value * @return the tree path */
public abstract TreePath getPath(Element e, AnnotationMirror a, AnnotationValue v);
Returns the Element for the Tree node identified by a given TreePath. Returns null if the element is not available.
Params:
  • path – the tree path
Throws:
Returns:the element
/** * Returns the Element for the Tree node identified by a given TreePath. * Returns {@code null} if the element is not available. * @param path the tree path * @return the element * @throws IllegalArgumentException is the TreePath does not identify * a Tree node that might have an associated Element. */
public abstract Element getElement(TreePath path);
Returns the TypeMirror for the Tree node identified by a given TreePath. Returns null if the TypeMirror is not available.
Params:
  • path – the tree path
Throws:
Returns:the type mirror
/** * Returns the TypeMirror for the Tree node identified by a given TreePath. * Returns {@code null} if the TypeMirror is not available. * @param path the tree path * @return the type mirror * @throws IllegalArgumentException is the TreePath does not identify * a Tree node that might have an associated TypeMirror. */
public abstract TypeMirror getTypeMirror(TreePath path);
Returns the Scope for the Tree node identified by a given TreePath. Returns null if the Scope is not available.
Params:
  • path – the tree path
Returns:the scope
/** * Returns the Scope for the Tree node identified by a given TreePath. * Returns {@code null} if the Scope is not available. * @param path the tree path * @return the scope */
public abstract Scope getScope(TreePath path);
Returns the doc comment, if any, for the Tree node identified by a given TreePath. Returns null if no doc comment was found.
Params:
  • path – the tree path
See Also:
Returns:the doc comment
/** * Returns the doc comment, if any, for the Tree node identified by a given TreePath. * Returns {@code null} if no doc comment was found. * @see DocTrees#getDocCommentTree(TreePath) * @param path the tree path * @return the doc comment */
public abstract String getDocComment(TreePath path);
Checks whether a given type is accessible in a given scope.
Params:
  • scope – the scope to be checked
  • type – the type to be checked
Returns:true if type is accessible
/** * Checks whether a given type is accessible in a given scope. * @param scope the scope to be checked * @param type the type to be checked * @return true if {@code type} is accessible */
public abstract boolean isAccessible(Scope scope, TypeElement type);
Checks whether the given element is accessible as a member of the given type in a given scope.
Params:
  • scope – the scope to be checked
  • member – the member to be checked
  • type – the type for which to check if the member is accessible
Returns:true if member is accessible in type
/** * Checks whether the given element is accessible as a member of the given * type in a given scope. * @param scope the scope to be checked * @param member the member to be checked * @param type the type for which to check if the member is accessible * @return true if {@code member} is accessible in {@code type} */
public abstract boolean isAccessible(Scope scope, Element member, DeclaredType type);
Returns the original type from the ErrorType object.
Params:
  • errorType – the errorType for which we want to get the original type
Returns:the type mirror corresponding to the original type, replaced by the ErrorType
/** * Returns the original type from the ErrorType object. * @param errorType the errorType for which we want to get the original type * @return the type mirror corresponding to the original type, replaced by the ErrorType */
public abstract TypeMirror getOriginalType(ErrorType errorType);
Prints a message of the specified kind at the location of the tree within the provided compilation unit
Params:
  • kind – the kind of message
  • msg – the message, or an empty string if none
  • t – the tree to use as a position hint
  • root – the compilation unit that contains tree
/** * Prints a message of the specified kind at the location of the * tree within the provided compilation unit * * @param kind the kind of message * @param msg the message, or an empty string if none * @param t the tree to use as a position hint * @param root the compilation unit that contains tree */
public abstract void printMessage(Diagnostic.Kind kind, CharSequence msg, com.sun.source.tree.Tree t, com.sun.source.tree.CompilationUnitTree root);
Returns the lub of an exception parameter declared in a catch clause.
Params:
  • tree – the tree for the catch clause
Returns:the lub of the exception parameter
/** * Returns the lub of an exception parameter declared in a catch clause. * @param tree the tree for the catch clause * @return the lub of the exception parameter */
public abstract TypeMirror getLub(CatchTree tree); }