-
Notifications
You must be signed in to change notification settings - Fork 0
Expand file tree
/
Copy pathindex.html
More file actions
316 lines (271 loc) · 15.1 KB
/
index.html
File metadata and controls
316 lines (271 loc) · 15.1 KB
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
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
<!doctype html>
<html lang="en">
<head>
<meta charset="utf-8" />
<meta name="viewport" content="width=1024" />
<meta name="apple-mobile-web-app-capable" content="yes" />
<title>bytecode manipulation ... with ASM and cglib</title>
<meta name="author" content="Pawel Koperek" />
<link href="http://fonts.googleapis.com/css?family=Open+Sans:regular,semibold,italic,italicsemibold|PT+Sans:400,700,400italic,700italic|PT+Serif:400,700,400italic,700italic" rel="stylesheet" />
<link href="css/presentation.css" rel="stylesheet" />
<link rel="shortcut icon" href="favicon.png" />
<link rel="apple-touch-icon" href="apple-touch-icon.png" />
<head/>
<body class="impress-not-supported">
<div class="fallback-message">
<p>Your browser <b>doesn't support the features required</b> by impress.js, so you are presented with a simplified version of this presentation.</p>
<p>For the best experience please use the latest <b>Chrome</b>, <b>Safari</b> or <b>Firefox</b> browser.</p>
</div>
<div id="impress">
<div id="title" class="step slide" data-x="0" data-y="0">
<div class="presentation_title">
<span class="bytecode">bytecode</span> <span class="manipulation">m<span class="aletter">a</span>nipu<span class="lletter">l</span>atio<span class="nletter">n</span></span>
</div>
<div class="right">
<span>... with cglib and ASM</span>
</div>
<div class="title_author"><span class="date">05.2014</span><span class="slash">/</span><span class="author">Pawel Koperek</span></div>
</div>
<div id="why" class="step slide" data-x="0" data-y="-1000">
<div class="vcenter">
<div class="slide-header">why?</div>
<div class="slide-content">
<ul class="lv0_indent">
<li>tests (<a href="https://code.google.com/p/mockito/">mockito</a>, <a href="http://pitest.org/">pitest</a>)</li>
<li>static analysis (<a href="http://findbugs.sourceforge.net/">findbugs</a>)</li>
<li>aop (logging, security etc.)</li>
<li>new languages on jvm
(<a href="http://www.scala-lang.org/">scala</a>,
<a href="http://groovy.codehaus.org/">groovy</a>,
<a href="http://jruby.org/">jruby</a>)
</li>
<li>new cool tools (<a href="http://zeroturnaround.com/software/jrebel">jrebel</a>)
</ul>
</div>
</div>
</div>
<div id="example-src" class="step slide" data-x="0" data-y="-2000">
<div class="slide-header">bytecode sample</div>
<div id="bytecode-sample" class="slide-content">
<div class="src-java">
<pre style="color:#586e75">
<span style="color:#a57800">public</span> <span style="color:#a57800">class</span> <span style="color:#268bd2">HelloWorld</span> {
<span style="color:#a57800">public</span> <span style="color:#a57800">static</span> <span style="color:#073642;">void</span> <span style="color:#268bd2">main</span>(<span style="color:#073642">String</span>[] args) {
<span style="color:#073642">System</span><span style="color:#859900">.</span>out<span style="color:#859900">.</span>println(<span style="color:#269186"><span style="color:#c60000">"</span>Woohoo!<span style="color:#c60000">"</span></span>);
}
}
</pre>
</div>
</div>
<div class="sh-cmd">
$ javac HelloWorld.java
</div>
</div>
<div id="example-bytecode-hex" class="step slide" data-x="0" data-y="-2000">
<div id="hex">
<pre>
00000000 ca fe ba be 00 00 00 33 00 15 0a 00 04 00 11 09 |.......3........|
00000010 00 03 00 12 07 00 13 07 00 14 01 00 05 66 69 65 |.............fie|
00000020 6c 64 01 00 01 49 01 00 06 3c 69 6e 69 74 3e 01 |ld...I...<init>.|
00000030 00 03 28 29 56 01 00 04 43 6f 64 65 01 00 0f 4c |..()V...Code...L|
00000040 69 6e 65 4e 75 6d 62 65 72 54 61 62 6c 65 01 00 |ineNumberTable..|
00000050 08 67 65 74 46 69 65 6c 64 01 00 03 28 29 49 01 |.getField...()I.|
00000060 00 08 73 65 74 46 69 65 6c 64 01 00 04 28 49 29 |..setField...(I)|
00000070 56 01 00 0a 53 6f 75 72 63 65 46 69 6c 65 01 00 |V...SourceFile..|
00000080 0d 4e 65 77 43 6c 61 73 73 2e 6a 61 76 61 0c 00 |.NewClass.java..|
00000090 07 00 08 0c 00 05 00 06 01 00 08 4e 65 77 43 6c |...........NewCl|
000000a0 61 73 73 01 00 10 6a 61 76 61 2f 6c 61 6e 67 2f |ass...java/lang/|
000000b0 4f 62 6a 65 63 74 00 21 00 03 00 04 00 00 00 01 |Object.!........|
000000c0 00 02 00 05 00 06 00 00 00 03 00 01 00 07 00 08 |................|
000000d0 00 01 00 09 00 00 00 1d 00 01 00 01 00 00 00 05 |................|
000000e0 2a b7 00 01 b1 00 00 00 01 00 0a 00 00 00 06 00 |*...............|
000000f0 01 00 00 00 01 00 01 00 0b 00 0c 00 01 00 09 00 |................|
00000100 00 00 1d 00 01 00 01 00 00 00 05 2a b4 00 02 ac |...........*....|
00000110 00 00 00 01 00 0a 00 00 00 06 00 01 00 00 00 05 |................|
00000120 00 01 00 0d 00 0e 00 01 00 09 00 00 00 22 00 02 |............."..|
00000130 00 02 00 00 00 06 2a 1b b5 00 02 b1 00 00 00 01 |......*.........|
00000140 00 0a 00 00 00 0a 00 02 00 00 00 09 00 05 00 0a |................|
00000150 00 01 00 0f 00 00 00 02 00 10 |..........|
</pre>
</div>
</div>
<div id="example-bytecode" class="step slide" data-x="0" data-y="-2000">
<div class="slide-content">
<div class="sh-cmd">
$ javap -c HelloWorld.class
</div>
<div class="src-java">
<pre style="color:#586e75"><span style="color:#a57800">public</span> <span style="color:#a57800">class</span> <span style="color:#268bd2">HelloWorld</span> {
<span style="color:#a57800">public</span> <span style="color:#268bd2">HelloWorld</span>();
<span style="color:#073642;font-weight:700">Code</span><span style="color:#859900">:</span>
<span style="color:#d33682">0</span><span style="color:#859900">:</span> aload_0
<span style="color:#d33682">1</span>: invokespecial #<span style="color:#d33682">1</span> <span style="color:#93a1a1">// Method java/lang/Object."<init>":()V</span>
<span style="color:#d33682">4</span>: return
<span style="color:#a57800">public</span> <span style="color:#a57800">static</span> <span style="color:#073642;font-weight:700">void</span> <span style="color:#268bd2">main</span>(<span style="color:#073642;font-weight:700">java.lang.String</span>[]);
<span style="color:#073642;font-weight:700">Code</span><span style="color:#859900">:</span>
<span style="color:#d33682">0</span><span style="color:#859900">:</span> getstatic #<span style="color:#d33682">2</span> <span style="color:#93a1a1">// Field java/lang/System.out:Ljava/io/PrintStream;</span>
<span style="color:#d33682">3</span><span style="color:#859900">:</span> ldc #<span style="color:#d33682">3</span> <span style="color:#93a1a1">// String Woohoo!</span>
<span style="color:#d33682">5</span>: invokevirtual #<span style="color:#d33682">4</span>
<span style="color:#93a1a1">// Method java/io/PrintStream.println:(Ljava/lang/String;)V</span>
<span style="color:#d33682">8</span><span style="color:#859900">:</span> return
}
</pre>
</div>
</div>
</div>
<div id="example-bytecode-ctor" class="step overlay" data-x="0" data-y="-2000">
<div id="mark-default-ctor" class="mark"></div>
</div>
<div id="example-bytecode-aload0" class="step overlay" data-x="0" data-y="-2000">
<div id="mark-aload0">
<div class="comment">
pushes "this" on stack
</div>
<div class="mark"></div>
</div>
</div>
<div id="stacks-diagram" class="step overlay" data-x="-1250" data-y="-2000">
<div id="stacks-diagram-ctr"></div>
</div>
<div id="example-bytecode-invokespecial" class="step overlay" data-x="0" data-y="-2000">
<div id="mark-invokespecial">
<div class="comment">
#1 refers to <em>Constant Pool</em> <br><br>
invokes a "special" method (constructors, initialization blocks, private methods)
</div>
<div class="mark"></div>
</div>
</div>
<div id="example-bytecode-return" class="step overlay" data-x="0" data-y="-2000">
<div id="mark-return">
<div class="comment">
explicit return
</div>
<div class="mark"></div>
</div>
</div>
<div id="example-bytecode-getstatic" class="step overlay" data-x="0" data-y="-2000">
<div id="mark-getstatic">
<div class="comment">
retrieves value of static field and pushes on stack
</div>
<div class="mark"></div>
</div>
</div>
<div id="example-bytecode-ldc" class="step overlay" data-x="0" data-y="-2000">
<div id="mark-ldc">
<div class="comment">
pushes constant from <em>Constant Pool</em> on stack
</div>
<div class="mark"></div>
</div>
</div>
<div id="example-bytecode-invokevirtual" class="step overlay" data-x="0" data-y="-2000">
<div id="mark-invokevirtual">
<div class="comment">
invokes a virtual method (considers method overriding)
</div>
<div class="mark"></div>
</div>
</div>
<div id="example-intercept" class="step slide" data-x="0" data-y="-3000">
<div class="slide-header">intercept a method</div>
<div class="slide-content">
<div id="class-to-intercept" class="src-java">
<pre style="color:#586e75"><span style="color:#a57800">class</span> <span style="color:#268bd2">ClassToBeIntercepted</span> {
<span style="color:#a57800">public</span> <span style="color:#073642;font-weight:700">void</span> <span style="color:#268bd2">toCallOne</span>() {
<span style="color:#073642;font-weight:700">System</span><span style="color:#859900">.</span>out<span style="color:#859900">.</span>println(<span style="color:#269186"><span style="color:#c60000">"</span>toCallOne<span style="color:#c60000">"</span></span>);
}
<span style="color:#a57800">public</span> <span style="color:#073642;font-weight:700">void</span> <span style="color:#268bd2">toCallTwo</span>() {
<span style="color:#073642;font-weight:700">System</span><span style="color:#859900">.</span>out<span style="color:#859900">.</span>println(<span style="color:#269186"><span style="color:#c60000">"</span>toCallTwo<span style="color:#c60000">"</span></span>);
}
}
</pre>
</div>
</div>
</div>
<div id="example-create-class" class="step slide" data-x="0" data-y="-4000">
<div class="slide-header">create new class</div>
<div class="slide-content">
<div id="new-class" class="src-java">
<pre style="color:#586e75">
<span style="color:#a57800">public</span> <span style="color:#a57800">class</span> <span style="color:#268bd2">NewClass</span> {
<span style="color:#a57800">private</span> <span style="color:#073642;font-weight:700">int</span> field;
<span style="color:#a57800">public</span> <span style="color:#073642;font-weight:700">int</span> <span style="color:#268bd2">getField</span>() {
<span style="color:#859900">return</span> field;
}
<span style="color:#a57800">public</span> <span style="color:#073642;font-weight:700">void</span> <span style="color:#268bd2">setField</span>(<span style="color:#073642;font-weight:700">int</span> field) {
<span style="color:#268bd2">this</span><span style="color:#859900">.</span>field <span style="color:#859900">=</span> field;
}
}
</pre>
</div>
</div>
</div>
<div id="example-final" class="step slide" data-x="0" data-y="-5000">
<div class="slide-header">override a private method in a final class</div>
<div class="slide-content">
<div id="final-class" class="src-java">
<pre style="color:#586e75">
<span style="color:#a57800">public</span> <span style="color:#a57800">final</span> <span style="color:#a57800">class</span> <span style="color:#268bd2">FinalClass</span> {
<span style="color:#a57800">private</span> <span style="color:#073642;font-weight:700">void</span> <span style="color:#268bd2">hardToCallMe</span>() {
<span style="color:#073642;font-weight:700">System</span><span style="color:#859900">.</span>out<span style="color:#859900">.</span>println(<span style="color:#269186"><span style="color:#c60000">"</span>inside hardToCallMe<span style="color:#c60000">"</span></span>);
}
<span style="color:#a57800">public</span> <span style="color:#073642;font-weight:700">void</span> <span style="color:#268bd2">callMe</span>() {
<span style="color:#073642;font-weight:700">System</span><span style="color:#859900">.</span>out<span style="color:#859900">.</span>println(<span style="color:#269186"><span style="color:#c60000">"</span>inside callMe<span style="color:#c60000">"</span></span>);
hardToCallMe();
}
}
</pre>
</div>
</div>
</div>
<div id="good-practises" class="step slide" data-x="0" data-y="-6000">
<div class="vcenter">
<div class="slide-header">
good practices
</div>
<div class="slide-content">
<ul class="lv0_indent">
<li>when possible - use higher level libraries (<em>cglib</em>)</li>
<li>write as much as possible in Java (invoke methods in instrumentation code only)</li>
<li>don't write all of ASM code by yourself: write it in pure Java and use <em>javap</em> or <em>ASMifier</em></li>
</ul>
</div>
</div>
</div>
<div id="sources" class="step slide" data-x="0" data-y="-7000">
<div class="vcenter">
<div class="slide-header">
sources
</div>
<div class="slide-content">
<ul class="lv0_indent">
<li><a href="http://docs.oracle.com/javase/specs/jvms/se7/html/">JVM specification</a></li>
<li><a href="http://blog.jamesdbloom.com/JVMInternals.html">JVM internals by James Bloom</a></li>
<li><a href="http://asm.ow2.org/">ASM</a></li>
<li><a href="https://github.com/cglib/cglib">cglib</a></li>
</ul>
</div>
</div>
</div>
<div id="questions" class="step slide" data-x="0" data-y="-8000">
<div class="ex-title">questions?</div>
</div>
<div id="thanks" class="step slide" data-x="0" data-y="-9000">
<div class="ex-title">thanks!</div>
</div>
</div>
<div class="hint">
<p>Use a spacebar or arrow keys to navigate</p>
</div>
<script>
if ("ontouchstart" in document.documentElement) {
document.querySelector(".hint").innerHTML = "<p>Tap on the left or right to navigate</p>";
}
</script>
<script src="js/impress.js"></script>
<script>impress().init();</script>
<script src="js/main.js"></script>
</body>
</html>