src/share/jaxws_classes/com/sun/codemodel/internal/package-info.java

Thu, 12 Oct 2017 19:44:07 +0800

author
aoqi
date
Thu, 12 Oct 2017 19:44:07 +0800
changeset 760
e530533619ec
parent 0
373ffda63c9a
permissions
-rw-r--r--

merge

     1 /*
     2  * Copyright (c) 1997, 2010, Oracle and/or its affiliates. All rights reserved.
     3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
     4  *
     5  * This code is free software; you can redistribute it and/or modify it
     6  * under the terms of the GNU General Public License version 2 only, as
     7  * published by the Free Software Foundation.  Oracle designates this
     8  * particular file as subject to the "Classpath" exception as provided
     9  * by Oracle in the LICENSE file that accompanied this code.
    10  *
    11  * This code is distributed in the hope that it will be useful, but WITHOUT
    12  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
    13  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
    14  * version 2 for more details (a copy is included in the LICENSE file that
    15  * accompanied this code).
    16  *
    17  * You should have received a copy of the GNU General Public License version
    18  * 2 along with this work; if not, write to the Free Software Foundation,
    19  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
    20  *
    21  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
    22  * or visit www.oracle.com if you need additional information or have any
    23  * questions.
    24  */
    26 /**
    27  * <h1>Library for generating Java source code</h1>.
    28  *
    29  * <p>
    30  * CodeModel is a library that allows you to generate Java source
    31  * code in a type-safe fashion.
    32  *
    33  * <p>
    34  * With CodeModel, you build the java source code by first building AST,
    35  * then writing it out as text files that is Java source files.
    36  * The AST looks like this:
    37  *
    38  * {@DotDiagram
    39     digraph G {
    40         cls1 [label="JDefinedClass"];
    41         cls2 [label="JDefinedClass"];
    42         JCodeModel -> cls1 [label="generated class"];
    43         JCodeModel -> cls2 [label="generated class"];
    45         m1 [label="JMethod"];
    46         m2 [label="JMethod"];
    48         cls1 -> m1;
    49         cls1 -> m2;
    50         cls1 -> JField;
    52         m1 -> JVar [label="method parameter"];
    53         m1 -> JBlock [label="code"];
    54     }
    55  * }
    56  *
    57  * <p>
    58  * You bulid this tree mostly from top-down. So, you first create
    59  * a new {@link JDefinedClass} from {@link JCodeModel}, then you
    60  * create a {@link JMethod} from {@link JDefinedClass}, and so on.
    61  *
    62  * <p>
    63  * This design brings the following beneefits:
    64  *
    65  * <ul>
    66  *  <li>source code can be written in random order
    67  *  <li>generated source code nicely imports other classes
    68  *  <li>generated source code is lexically always correct
    69  *      (no unbalanced parenthesis, etc.)
    70  *  <li>code generation becomes relatively type-safe
    71  * </ul>
    72  *
    73  * The price you pay for that is
    74  * increased memory footprint and the generation speed.
    75  * See <a href="#performance">performance section</a> for
    76  * more discussions about the performance and possible improvements.
    77  *
    78  *
    79  * <h2>Using CodeModel</h2>
    80  * <p>
    81  * {@link com.sun.codemodel.internal.JCodeModel} is the entry point to
    82  * the library. See its javadoc for more details about how to use
    83  * CodeModel.
    84  *
    85  *
    86  *
    87  * <h2>Performance</h2>
    88  * <p>
    89  * Generally speaking, CodeModel is expected to be used in
    90  * an environment where the resource constraint is not severe.
    91  * Therefore, we haven't spent much effort in trying to make
    92  * this library lean and mean.
    93  *
    94  * <p>
    95  * That said, we did some benchmark and performance analysis.
    96  * In case anyone is interested in making this library
    97  * better performance wise, here's the findings.
    98  *
    99  * <p>
   100  * {@link List}s {@link Map}s, and other collections take up
   101  * a lot of space. Allocating those things lazily is generally
   102  * a good idea.
   103  *
   104  * <p>
   105  * Compared to template-based code generator, the writing operation
   106  * is slow, as it needs to traverse each AST node. Consider
   107  * pre-encoding tokens (like 'public') to the target encoding,
   108  * and consider exploting the subtree equivalence.
   109  *
   110  * @ArchitectureDocument
   111  */
   112 package com.sun.codemodel.internal;
   114 import java.util.List;
   115 import java.util.Map;

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