javaquery/api/src/main/java/org/apidesign/bck2brwsr/htmlpage/ConvertTypes.java
author Jaroslav Tulach <jaroslav.tulach@apidesign.org>
Fri, 05 Apr 2013 12:43:17 +0200
branchmodel
changeset 934 19b4ddc302a6
parent 920 e2977ec1ef6e
child 941 d1e482f73507
permissions -rw-r--r--
@OnReceive annotation can obtain and process single JSON object
     1 /**
     2  * Back 2 Browser Bytecode Translator
     3  * Copyright (C) 2012 Jaroslav Tulach <jaroslav.tulach@apidesign.org>
     4  *
     5  * This program is free software: you can redistribute it and/or modify
     6  * it under the terms of the GNU General Public License as published by
     7  * the Free Software Foundation, version 2 of the License.
     8  *
     9  * This program is distributed in the hope that it will be useful,
    10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
    11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    12  * GNU General Public License for more details.
    13  *
    14  * You should have received a copy of the GNU General Public License
    15  * along with this program. Look for COPYING file in the top folder.
    16  * If not, see http://opensource.org/licenses/GPL-2.0.
    17  */
    18 package org.apidesign.bck2brwsr.htmlpage;
    19 
    20 import org.apidesign.bck2brwsr.core.JavaScriptBody;
    21 
    22 /**
    23  *
    24  * @author Jaroslav Tulach <jtulach@netbeans.org>
    25  */
    26 public final class ConvertTypes {
    27     ConvertTypes() {
    28     }
    29     
    30     public static String toString(Object object, String property) {
    31         Object ret = getProperty(object, property);
    32         return ret == null ? null : ret.toString();
    33     }
    34 
    35     public static double toDouble(Object object, String property) {
    36         Object ret = getProperty(object, property);
    37         return ret instanceof Number ? ((Number)ret).doubleValue() : Double.NaN;
    38     }
    39 
    40     public static int toInt(Object object, String property) {
    41         Object ret = getProperty(object, property);
    42         return ret instanceof Number ? ((Number)ret).intValue() : Integer.MIN_VALUE;
    43     }
    44 
    45     public static <T> T toModel(Class<T> modelClass, Object object, String property) {
    46         Object ret = getProperty(object, property);
    47         if (ret == null || modelClass.isInstance(ret)) {
    48             return modelClass.cast(ret);
    49         }
    50         throw new IllegalStateException("Value " + ret + " is not of type " + modelClass);
    51     }
    52     
    53     public static String toJSON(Object value) {
    54         if (value == null) {
    55             return "null";
    56         }
    57         if (value instanceof String) {
    58             return '"' + 
    59                 ((String)value).
    60                     replace("\"", "\\\"").
    61                     replace("\n", "\\n").
    62                     replace("\r", "\\r").
    63                     replace("\t", "\\t")
    64                 + '"';
    65         }
    66         return value.toString();
    67     }
    68     
    69     @JavaScriptBody(args = { "object", "property" },
    70         body = "if (property === null) return object;\n"
    71         + "var p = object[property]; return p ? p : null;"
    72     )
    73     private static Object getProperty(Object object, String property) {
    74         return null;
    75     }
    76 
    77     @JavaScriptBody(args = { "url", "arr", "callback" }, body = ""
    78         + "var request = new XMLHttpRequest();\n"
    79         + "request.open('GET', url, true);\n"
    80         + "request.setRequestHeader('Content-Type', 'application/json; charset=utf-8');\n"
    81         + "request.onreadystatechange = function() {\n"
    82         + "  if (this.readyState!==4) return;\n"
    83         + "  arr[0] = eval('(' + this.response + ')');\n"
    84         + "  callback.run__V();\n"
    85         + "};"
    86         + "request.send();"
    87     )
    88     public static native void loadJSON(
    89         String url, Object[] jsonResult, Runnable whenDone
    90     );
    91     
    92     public static void extractJSON(Object jsonObject, String[] props, Object[] values) {
    93         for (int i = 0; i < props.length; i++) {
    94             values[i] = getProperty(jsonObject, props[i]);
    95         }
    96     }
    97     
    98 }