langtools/src/share/opensource/javac/doc/javac_lifecycle/Enter.html
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+<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
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+
+<html>
+    <head>
+        <meta http-equiv="content-type" content="text/html; charset=ISO-8859-1">
+        <meta name="author" content="Jonathan Gibbons">
+        <link type="text/css" rel=stylesheet href="style.css">
+        <title>com.sun.tools.javac.comp.Enter</title>
+    </head>
+    <body>
+
+        <h3>com.sun.tools.javac.comp.Enter</h3>
+
+        This enters symbols for all encountered definitions into
+        the symbol table. The pass consists of two phases, organized as
+        follows:
+
+        <ol>
+            <li><p>In the first phase, all class symbols are entered into their
+            enclosing scope, descending recursively down the tree for classes
+            which are members of other classes. The class symbols are given a
+            MemberEnter object as completer.</p></li>
+  
+            <p><a name="package-info"></a>In addition, 
+                if any <span class=code>package-info.java</span> files are found, 
+                containing package annotations, then the TopLevel tree node for 
+                the package-info.java file is put on the "to do" as well.
+            </p>
+
+            <li><p>In the second phase, classes are completed using
+            MemberEnter.complete().  Completion might occur on demand, but
+            any classes that are not completed that way will be eventually
+            completed by processing the `uncompleted' queue.  Completion
+            entails 
+            <ul><li>(1) determination of a class's parameters, supertype and
+                interfaces, as well as <li>(2) entering all symbols defined in the
+                class into its scope, with the exception of class symbols which
+                have been entered in phase 1.</li>
+            </ul>
+            (2) depends on (1) having been
+            completed for a class and all its superclasses and enclosing
+            classes. That's why, after doing (1), we put classes in a
+            `halfcompleted' queue. Only when we have performed (1) for a class
+            and all it's superclasses and enclosing classes, we proceed to
+            (2).</p></li>
+        </ol>
+ 
+        <p>Whereas the first phase is organized as a sweep through all
+        compiled syntax trees, the second phase is demand. Members of a
+        class are entered when the contents of a class are first
+        accessed. This is accomplished by installing completer objects in
+        class symbols for compiled classes which invoke the member-enter
+        phase for the corresponding class tree.</p>
+ 
+        <p>Classes migrate from one phase to the next via queues:</p>
+ 
+        <pre>
+    class enter -> (Enter.uncompleted)         --> member enter (1)
+ 		-> (MemberEnter.halfcompleted) --> member enter (2)
+ 		-> (Todo)	               --> attribute
+ 						(only for toplevel classes)
+        </pre>
+
+    </body>
+</html>
+