1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
|
/*
* Copyright (C) 2009-2011 Mathias Doenitz
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package spray.json
import annotation.tailrec
import java.lang.StringBuilder
/**
* A JsonPrinter serializes a JSON AST to a String.
*/
trait JsonPrinter extends (JsValue => String) {
def apply(x: JsValue): String = apply(x, None)
def apply(x: JsValue, jsonpCallback: String): String = apply(x, Some(jsonpCallback))
def apply(x: JsValue, jsonpCallback: Option[String]): String = {
val sb = new StringBuilder
jsonpCallback match {
case Some(callback) => {
sb.append(callback).append('(')
print(x, sb)
sb.append(')');
}
case None => print(x, sb)
}
sb.toString
}
def print(x: JsValue, sb: StringBuilder)
protected def printLeaf(x: JsValue, sb: StringBuilder) {
x match {
case JsNull => sb.append("null")
case JsTrue => sb.append("true")
case JsFalse => sb.append("false")
case JsNumber(x) => sb.append(x)
case JsString(x) => printString(x, sb)
case _ => throw new IllegalStateException
}
}
protected def printString(s: String, sb: StringBuilder) {
import JsonPrinter._
@tailrec def firstToBeEncoded(ix: Int = 0): Int =
if (ix == s.length) -1 else if (requiresEncoding(s.charAt(ix))) ix else firstToBeEncoded(ix + 1)
sb.append('"')
firstToBeEncoded() match {
case -1 ⇒ sb.append(s)
case first ⇒
sb.append(s, 0, first)
@tailrec def append(ix: Int): Unit =
if (ix < s.length) {
s.charAt(ix) match {
case c if !requiresEncoding(c) => sb.append(c)
case '"' => sb.append("\\\"")
case '\\' => sb.append("\\\\")
case '\b' => sb.append("\\b")
case '\f' => sb.append("\\f")
case '\n' => sb.append("\\n")
case '\r' => sb.append("\\r")
case '\t' => sb.append("\\t")
case x if x <= 0xF => sb.append("\\u000").append(Integer.toHexString(x))
case x if x <= 0xFF => sb.append("\\u00").append(Integer.toHexString(x))
case x if x <= 0xFFF => sb.append("\\u0").append(Integer.toHexString(x))
case x => sb.append("\\u").append(Integer.toHexString(x))
}
append(ix + 1)
}
append(first)
}
sb.append('"')
}
protected def printSeq[A](iterable: Iterable[A], printSeparator: => Unit)(f: A => Unit) {
var first = true
iterable.foreach { a =>
if (first) first = false else printSeparator
f(a)
}
}
}
object JsonPrinter {
private[this] val mask = new Array[Int](4)
private[this] def ascii(c: Char): Int = c & ((c - 127) >> 31) // branchless for `if (c <= 127) c else 0`
private[this] def mark(c: Char): Unit = {
val b = ascii(c)
mask(b >> 5) |= 1 << (b & 0x1F)
}
private[this] def mark(range: scala.collection.immutable.NumericRange[Char]): Unit = range foreach (mark)
mark('\u0000' to '\u001f')
mark('\u007f')
mark('"')
mark('\\')
def requiresEncoding(c: Char): Boolean = {
val b = ascii(c)
(mask(b >> 5) & (1 << (b & 0x1F))) != 0
}
}
|
