Component Development for the Java Platform Book

	Foreword	xiii
	Preface	xv
1	From Objects to Components	1
2	The Class Loader Architecture	11
2.1	Assembling an Application	11
2.2	Goals of the Class Loader Architecture	14
2.2.1	Transparency	15
2.2.2	Extensibility	15
2.2.3	Capability	16
2.2.4	Configurability	16
2.2.5	Handling Name and Version Conflicts	16
2.2.6	Security	17
2.3	Explicit and Implicit Class Loading	17
2.3.1	Explicit Loading with URL ClassLoader	18
2.3.2	Implicit Class Loading	19
2.3.3	Reference Type versus Referenced Class	20
2.3.4	ClassLoader.loadClass versus Class.forName	21
2.3.5	Loading Nonclass Resources	22
2.4	The Class Loader Rules	23
2.4.1	The Consistency Rule	23
2.4.2	The Delegation Rule	24
2.4.3	The Visibility Rule	25
2.4.4	Delegations as Namespaces	27
2.4.5	Static Fields Are Not Singletons	28
2.4.6	Implicit Loading Hides Most Details	29
2.5	Hot Deployment	29
2.5.1	Using Hot Deployment	33
2.6	Unloading Classes	35
2.6.1	Making Sure Classes Are Collectable	35
2.7	Bootclasspath, Extensions Path, and Classpath	36
2.7.1	The Classpath	37
2.7.2	The Extensions Path	39
2.7.3	The Bootclasspath	41
2.8	Debugging Class Loading	43
2.8.1	Instrumenting an Application	44
2.8.2	Using--verbose:class	45
2.8.3	Instrumenting the Core API	46
2.9	Inversion and the Context Class Loader	49
2.10	Onward	55
2.11	Resources	56
3	Type Information and Reflection	57
3.1	The Binary Class Format	58
3.1.1	Binary Compatibility	58
3.1.2	Binary Class Metadata	63
3.1.3	From Binary Classes to Reflection	66
3.2	Reflection	66
3.2.1	Reflecting on Fields	68
3.2.2	The Difference between get and getDeclared	68
3.2.3	Type Errors Occur at Runtime	70
3.2.4	Reflecting on Methods	71
3.3	Reflective Invocation	72
3.3.1	A Reflective Launcher	73
3.3.2	Wrapping Primitive Types	74
3.3.3	Bypassing Language Access Rules	76
3.3.4	Exceptions Caused by Reflective Invocation	81
3.4	Dynamic Proxies	83
3.4.1	Delegation instead of Implementation Inheritance	83
3.4.2	Dynamic Proxies Make Delegation Generic	84
3.4.3	Implementing InvocationHandler	85
3.4.4	Implementing a Forwarding Handler	86
3.4.5	The InvocationHandler as Generic Service	87
3.4.6	Handling Exceptions in an InvocationHandler	89
3.4.7	Either Client or Server Can Install a Proxy	90
3.4.8	Advantages of Dynamic Proxies	91
3.5	Reflection Performance	92
3.6	Package Reflection	94
3.6.1	Setting Package Metadata	95
3.6.2	Accessing Package Metadata	96
3.6.3	Sealing Packages	97
3.6.4	Weaknesses of the Versioning Mechanism	97
3.7	Custom Metadata	98
3.8	Onward	103
3.9	Resources	103
4	Serialization	105
4.1	Serialization and Metadata	105
4.2	Serialization Basics	106
4.2.1	Serialization Skips Some Fields	109
4.2.2	Serialization and Class Constructors	110
4.3	Using readObject and writeObject	111
4.4	Matching Streams with Classes	113
4.4.1	The serialVersionUID	114
4.4.2	Overriding the Default SUID	115
4.4.3	Compatible and Incompatible Changes	117
4.5	Explicitly Managing Serializable Fields	119
4.5.1	ObjectInputStream. GetField Caveats	120
4.5.2	Writer Makes Right	121
4.5.3	Overriding Class Metadata	122
4.5.4	Performance Problems	123
4.5.5	Custom Class Descriptors	124
4.6	Abandoning Metadata	124
4.6.1	Writing Custom Data after defaultWriteObject	124
4.6.2	Externalizable	125
4.6.3	Using writeObject to Write Raw Data Only: Bad Idea	128
4.7	Object Graphs	130
4.7.1	Pruning Graphs with Transient	131
4.7.2	Preserving Identity	131
4.7.3	Encouraging the Garbage Collector with reset	132
4.8	Object Replacement	133
4.8.1	Stream-Controlled Replacement	134
4.8.2	Class-Controlled Replacement	137
4.8.3	Ordering Rules for Replacement	139
4.8.4	Taking Control of Graph Ordering	145
4.9	Finding Class Code	147
4.9.1	Annotation in RMI	148
4.9.2	RMI MarshalledObjects	150
4.10	Onward	150
4.11	Resources	151
5	Customizing Class Loading	153
5.1	Java 2 Security	155
5.1.1	The Role of Class Loaders	157
5.2	Custom Class Loaders	159
5.2.1	Pre-Java 2 Custom Class Loaders	159
5.2.2	Class Loading since SDK 1.2	160
5.2.3	A Transforming Class Loader	162
5.3	Protocol Handlers	168
5.3.1	Implementing a Handler	169
5.3.2	Installing a Custom Handler	171
5.3.3	Choosing between Loaders and Handlers	174
5.4	Getting Past Security to the Loader You Need	175
5.5	Reading Custom Metadata	177
5.5.1	Example: Version Attributes	178
5.5.2	Serializable Classes as Attributes	179
5.5.3	Reading Attributes during Class Loading	183
5.5.4	Debugging Support	188
5.6	Onward	189
5.7	Resources	190
6	Interop 1: JNI	191
6.1	Why Interoperate?	191
6.2	The Dangers of Native Code	193
6.3	Finding and Loading Native Code	194
6.3.1	Name Mappings	195
6.3.2	Type Mappings	195
6.3.3	Overloaded Names	198
6.3.4	Loading Native Libraries	199
6.3.5	Class Loaders and JNI	202
6.3.6	Common Errors Loading Native Libraries	205
6.3.7	Troubleshooting Native Loading	207
6.4	Calling Java from C++	208
6.4.1	Minimizing Round Trips	211
6.4.2	Performance Comparisons	214
6.4.3	Differences between JNI and Reflective Invocation	214
6.5	Error Handling in JNI	217
6.5.1	Failures in Native Code	217
6.5.2	Handling C++ Exceptions	218
6.5.3	Handling Java Exceptions from Native Code	219
6.5.4	Throwing Java Exceptions from Native Code	222
6.6	Resource Management	223
6.6.1	Interacting with the Garbage Collector	224
6.6.2	Managing Native Resources	231
6.6.3	Managing Arrays	233
6.6.4	Managing Strings	239
6.7	Onward	240
6.8	Resources	241
7	Generative Programming	243
7.1	Why Generate Code?	243
7.1.1	Object-Oriented Approaches to Modeling Variabilities	244
7.1.2	Thinking in Terms of Bind Time	246
7.1.3	Separating Specification from Bind Time	247
7.1.4	Choosing a Specification Language	249
7.1.5	Reuse Requires More Than One Use	249
7.1.6	A Little Domain Analysis Is a Dangerous Thing	250
7.2	Why Generate Code with Java?	250
7.2.1	Type Information Acts as a Free Specification Document	250
7.2.2	Class Loading Supports Flexible Binding Modes	251
7.2.3	Java Source Is Easy to Generate	251
7.2.4	Java Binary Classes Are Easy to Generate	252
7.2.5	Code Generation Boosts Performance	252
7.2.6	Levels of Commitment to Code Generation	252
7.3	A Taxonomy of Bind Times and Modes	253
7.4	Code Generation in RMI	255
7.5	Code Generation in JSP	257
7.6	Code Generation in EJB	260
7.6.1	The Deployment Descriptor	263
7.6.2	Alternate Implementations	265
7.7	Generating Strongly Typed Collections	267
7.7.1	Code Generation Language versus Target Language	270
7.8	Generating Custom Serialization Code	271
7.9	Onward	276
7.10	Resources	279
8	Onward	281
8.1	Where We Are	281
8.2	Where We Are Going	282
8.3	Resources	283
A	Interop 2: Bridging Java and Win32/COM	285
	Index	319