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Remove Dict_getAll since it is now unused

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`Dict_getAll` is problematic for a number of reasons. First of all, as issue 6961 shows, it can be really bad for performance, since it dereferences all indirect objects.
Second of all, all the derefencing can lead to data being unncessarily requested when ranged/chunked loading is used, thus unnecessarily delaying rendering.

Note: For cases where `Dict_getAll` was previously used, `Dict_getKeys` in combination with `Dict_get` can be used instead. This has the advantage that data isn't requested until it's actually needed.
This commit is contained in:
Jonas Jenwald 2016-02-12 18:16:45 +01:00
parent 93ea866f01
commit 1ee016b005
1 changed files with 0 additions and 70 deletions
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70
src/core/primitives.js
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@ -67,24 +67,6 @@ var Dict = (function DictClosure() {
return nonSerializable; // creating closure on some variable
};
var GETALL_DICTIONARY_TYPES_WHITELIST = {
'Background': true,
'ExtGState': true,
'Halftone': true,
'Layout': true,
'Mask': true,
'Pagination': true,
'Printing': true
};
function isRecursionAllowedFor(dict) {
if (!isName(dict.Type)) {
return true;
}
var dictType = dict.Type.name;
return GETALL_DICTIONARY_TYPES_WHITELIST[dictType] === true;
}
// xref is optional
function Dict(xref) {
// Map should only be used internally, use functions below to access.
@ -162,58 +144,6 @@ var Dict = (function DictClosure() {
return this.map[key];
},
// creates new map and dereferences all Refs
getAll: function Dict_getAll() {
var all = Object.create(null);
var queue = null;
var key, obj;
for (key in this.map) {
obj = this.get(key);
if (obj instanceof Dict) {
if (isRecursionAllowedFor(obj)) {
(queue || (queue = [])).push({target: all, key: key, obj: obj});
} else {
all[key] = this.getRaw(key);
}
} else {
all[key] = obj;
}
}
if (!queue) {
return all;
}
// trying to take cyclic references into the account
var processed = Object.create(null);
while (queue.length > 0) {
var item = queue.shift();
var itemObj = item.obj;
var objId = itemObj.objId;
if (objId && objId in processed) {
item.target[item.key] = processed[objId];
continue;
}
var dereferenced = Object.create(null);
for (key in itemObj.map) {
obj = itemObj.get(key);
if (obj instanceof Dict) {
if (isRecursionAllowedFor(obj)) {
queue.push({target: dereferenced, key: key, obj: obj});
} else {
dereferenced[key] = itemObj.getRaw(key);
}
} else {
dereferenced[key] = obj;
}
}
if (objId) {
processed[objId] = dereferenced;
}
item.target[item.key] = dereferenced;
}
return all;
},
getKeys: function Dict_getKeys() {
return Object.keys(this.map);
},