In a moment, the server should return the entire object graph
reachable from the root node in a binary tree each node of which
stores pointers to its parent, grandparent and two children. Each
node is numbered according to its position in a preorder traversal
of the tree. The data is serialized using JavaScript object notation
(JSON).
The potential problem of cycles in the object graph, which
would normally result in infinite recursion during serialization
or (if the object graph were pruned) duplicate references after
deserialization, is avoided by "flattening" the serialized object
graph. As the object graph is traversed during serialization, the
objects encountered are added to a "heap" of objects and all
object references are replaced with pointers into the heap. If
an object is encountered that is already on the heap, the reference
leading to it is replaced with the existing heap pointer and no
recursion results.
After the cycle-free representation of the object graph
has been retrieved asynchronously, the JSON is evaluated
and the graph reconnected. The root node of the binary tree
is presented below as a link that, when clicked, will display
its properties. Properties that reference other nodes in the tree
will be displayed as links as well, allowing you to navigate the
tree. Note that there is only one object in memory for each node
in the tree, regardless of how many other nodes reference it.
Deserialized Object(s)
Raw JSON from Server
Waiting for server...
PK
xB6h|5 json.jsfunction net_pauljm_json_Pointer(index) {
this.index = index;
}
function net_pauljm_json_deserialize(json) {
var values = new Array();
var state = eval("(" + json + ")");
for (var i = 0; i < state.heap.length; i ++) {
var value = state.heap[i];
if (value instanceof net_pauljm_json_Pointer) {
values[i] = state.heap[value.index];
} else if (typeof(value) == "object") {
for (var property in value) {
var propertyValue = value[property];
if (propertyValue instanceof net_pauljm_json_Pointer) {
value[property] = state.heap[propertyValue.index];
}
}
} else if (value instanceof Array) {
for (var j = 0; j < value.length; j ++) {
var element = value[j];
if (element instanceof net_pauljm_json_Pointer) {
value[j] = state.heap[element.index];
}
}
}
}
for (var i = 0; i < state.values.length; i ++) {
var value = state.values[i];
if (value instanceof net_pauljm_json_Pointer) {
values[i] = state.heap[value.index];
} else {
values[i] = value;
}
}
return values;
}PK
wB6x
json_test.jsp<%@page contentType="text/html"%><%--
--%><%@page pageEncoding="UTF-8"%><%--
--%><%@page import="net.pauljm.json.impl.JsonSerializerImpl"%><%--
--%><%@page import="net.pauljm.json.impl.test.JsonSerializerTest"%><%--
--%><%= new JsonSerializerTest().getSerializedGraph() %>PK
wB6. style.cssbody {
font-family: arial;
}
h1 {
margin: 10px 0;
padding: 5px 10px;
font-size: 1.3em;
font-weight: normal;
background-color: navy;
color: white;
}
p {
margin: 10px 0;
}
#intro {
margin: 10px 0 15px 20px;
}
#browser {
margin: 10px 0 15px 20px;
}
#json-view {
margin: 10px 0 15px 20px;
font-family: monospace;
white-space: pre;
color: rgb(102, 102, 102);
}PK
wB6 S4 4 ui.css.object-browser {
white-space: pre;
font-family: monospace;
}
.object-browser-value {
white-space: normal;
}
.object-browser-back-link {
margin-bottom: 10px;
font-weight: bold;
color: blue;
cursor: pointer;
}
.object-browser-value-link {
color: blue;
cursor: pointer;
}PK
wB6tJ_
ui.jsfunction net_pauljm_ui_clearChildren(element) {
while (element.childNodes.length > 0) {
element.removeChild(element.childNodes.item(0));
}
}
function net_pauljm_ui_setTextContent(element, text) {
net_pauljm_ui_clearChildren(element);
element.appendChild(document.createTextNode(text));
}
function net_pauljm_ui_ObjectBrowser() {
this.element = document.createElement("div");
this.element.className = "object-browser";
this.currentValue = null;
this.previousValue = null;
this.backLink = document.createElement("div");
this.backLink.className = "object-browser-back-link";
net_pauljm_ui_setTextContent(this.backLink, "<< back");
this.backLink.onclick = net_pauljm_util_bindFn(function() {
if (this.previousValue != null) {
this.open(this.previousValue, true);
}
}, this);
this.renderValue = function(value) {
var rendered = document.createElement("span");
rendered.className = " object-browser-value";
if (typeof(value) == "string") {
net_pauljm_ui_setTextContent(rendered, "\"" + value + "\"");
} else if (typeof(value) != "object") {
net_pauljm_ui_setTextContent(rendered, "" + value);
} else if (value == null) {
net_pauljm_ui_setTextContent(rendered, "null");
} else {
rendered.className += " object-browser-value-link";
rendered.onclick = net_pauljm_util_bindFn(function() {
this.open(value);
}, this);
if (value instanceof Array) {
net_pauljm_ui_setTextContent(rendered,
"Array(" + value.length + ")");
} else {
net_pauljm_ui_setTextContent(rendered, value.toString());
}
}
return rendered;
};
this.open = function(value, reset) {
if (reset) {
this.previousValue = null;
} else {
this.previousValue = this.currentValue;
}
this.currentValue = value;
net_pauljm_ui_clearChildren(this.element);
if (this.previousValue != null) {
this.element.appendChild(this.backLink);
}
if (typeof(value) == "string" || typeof(value) != "object") {
this.element.appendChild(this.renderValue(value));
} else if (value instanceof Array) {
this.element.appendChild(document.createTextNode("[\n"));
for (var i = 0; i < value.length; i ++) {
if (i != 0) {
this.element.appendChild(document.createTextNode(",\n"));
}
this.element.appendChild(document.createTextNode(" "));
this.element.appendChild(this.renderValue(value[i]));
}
this.element.appendChild(document.createTextNode("\n]"));
} else {
this.element.appendChild(document.createTextNode("{\n"));
var first = true;
for (var property in value) {
if (first) {
first = false;
} else {
this.element.appendChild(document.createTextNode(",\n"));
}
this.element.appendChild(document.createTextNode(" "
+ property + " : "));
this.element.appendChild(this.renderValue(value[property]));
}
this.element.appendChild(document.createTextNode("\n}"));
}
};
}PK
xB6j:r r util.jsfunction net_pauljm_util_bindFn(fn, object) {
return function() {
fn.apply(object, arguments);
}
}PK
xB6HD
xmlhttp.jsfunction net_pauljm_xmlhttp_withResponseText(url, callback) {
var req = false;
if(window.XMLHttpRequest) {
try {
req = new XMLHttpRequest();
} catch(e) {
req = false;
}
} else if (window.ActiveXObject) {
try {
req = new ActiveXObject("Msxml2.XMLHTTP");
} catch(e) {
try {
req = new ActiveXObject("Microsoft.XMLHTTP");
} catch(e) {
req = false;
}
}
}
if (!req) {
alert("Could not obtain XMLHttpRequest object");
return;
}
req.onreadystatechange = function() {
if (req.readyState == 4) {
if (req.status == 200) {
callback(req.responseText);
} else {
alert("There was a problem retrieving the XML data: "
+ req.status + ": " + req.statusText);
}
}
}
req.open("GET", url, true);
req.send("");
}PK
yB6 A META-INF/ PK
xB6 &qj j + META-INF/MANIFEST.MFPK
xB6 A WEB-INF/PK
xB6 A WEB-INF/classes/PK
xB6 A WEB-INF/classes/net/PK
xB6 AM WEB-INF/classes/net/pauljm/PK
xB6 A WEB-INF/classes/net/pauljm/json/PK
xB6 % A WEB-INF/classes/net/pauljm/json/impl/PK
xB6 * A WEB-INF/classes/net/pauljm/json/impl/test/PK
yB6 % AO WEB-INF/classes/net/pauljm/json/node/PK
wB6 A WEB-INF/lib/PK
wB6/? ? META-INF/context.xmlPK
xB6!oq q 9 - WEB-INF/classes/net/pauljm/json/CannotReadException.classPK
xB6x 1 WEB-INF/classes/net/pauljm/json/FieldReader.classPK
xB6z @ WEB-INF/classes/net/pauljm/json/JsonSerializationException.classPK
xB6L 4 D
WEB-INF/classes/net/pauljm/json/JsonSerializer.classPK
xB6# = N WEB-INF/classes/net/pauljm/json/UniversalJsonSerializer.classPK
xB6?
: WEB-INF/classes/net/pauljm/json/impl/FieldReaderImpl.classPK
xB6mqV V I WEB-INF/classes/net/pauljm/json/impl/InternalSerializationException.classPK
xB6a* * = ~ WEB-INF/classes/net/pauljm/json/impl/JsHeap$JsHeapEntry.classPK
xB6l ? # WEB-INF/classes/net/pauljm/json/impl/JsHeap$JsHeapPointer.classPK
xB6c=Um m 1 T& WEB-INF/classes/net/pauljm/json/impl/JsHeap.classPK
xB6Ѕ% 4 / WEB-INF/classes/net/pauljm/json/impl/JsPointer.classPK
xB6 A / WEB-INF/classes/net/pauljm/json/impl/JsSerializationContext.classPK
xB6 _h h = ,D WEB-INF/classes/net/pauljm/json/impl/JsonSerializerImpl.classPK
xB6 9 I WEB-INF/classes/net/pauljm/json/impl/test/GraphNode.classPK
xB6#/h D [P WEB-INF/classes/net/pauljm/json/impl/test/JsonSerializerTest$1.classPK
xB6 H O Q WEB-INF/classes/net/pauljm/json/impl/test/JsonSerializerTest$GraphContext.classPK
xB6!L B 'V WEB-INF/classes/net/pauljm/json/impl/test/JsonSerializerTest.classPK
xB6뮛 2 _ WEB-INF/classes/net/pauljm/json/node/JsArray.classPK
yB6-@ @ 4 nd WEB-INF/classes/net/pauljm/json/node/JsBoolean.classPK
xB6