CONTENTS
Preface	iii
Dedication	v
Chapter 1 The Robot World	1
1.1 The Robot World	1
1.2 Robot Capabilities	3
1.3 Tasks and Situations	4
1.4 Robots and Objects	4
1.5 Important Ideas From This Chapter	5
1.6 Problem Set	5
Chapter 2 Primitive Instructions and Simple Programs	7
2.1 Changing Position	7
2.2 Turning in Place	8
2.3 Finishing a Task	9
2.4 Handling Beepers	9
2.5 Robot Descriptions	9
2.6 A Complete Program	11
2.6.1 Executing a Program	12
2.6.2 The Form of Robot Programs	14
2.7 Error Shutoffs	15
2.8 Programming Errors	16
2.8.1 Bugs and Debugging	18
2.9 A Task for Two Robots	19
2.10 An infinity of Beepers	20
2.11 Some Terminology	20
2.12 Important Ideas From This Chapter	21
2.13 Problem Set	21
Chapter 3 Extending the Robot Programming Language	30
3.1 Creating a More Natural Programming Language	30
3.2 A Mechanism that Defines New Classes of Robots	31
3.3 Defining the New Methods	32
3.4 The Meaning and Correctness of New Methods	35
3.5 Defining New Methods in a Program	36
3.6 Modifying Inherited Methods	39
3.7 An Ungrammatical Program	41
3.8 Tools for Designing and Writing Robot Programs	42
3.8.1 Stepwise Refinement-a Technique for Planning, Implementing, and
Analyzing Robot Programs	42
3.8.2 The Second Step-Planning harvestTwoRows and positionForNextHarvest	46
3.8.3 The Third Step-Planning harvestOneRow and goToNextRow	48
3.8.4 The Final Step-Verifying That the Complete Program is Correct	50
3.9 Advantages of Using New Instructions	52
3.9.1 Avoiding Errors	53
3.9.2 Future Modifications	54
3.9.3 A Program Without New instructions	56
3.10 Writing Understandable Programs	58
3.11 Important Ideas From This Chapter	59
3.12 Problem Set	59
Chapter 4 Polymorphism	65
4.1 Robot Teams	65
4.2 Similar Tasks	67
4.3 Choreographers	70
4.4 Object Oriented Design -- Clients and Servers	73
4.5 Using Polymorphism	79
4.6 Still More on Polymorphism -- Strategy and Delegation	83
4.7 Java Enumerations and More on Strategies	89
4.8 Decorators	93
4.9 Observers	95
4.10 Final Words on Polymorphism	97
4.11 Important Ideas From This Chapter	98
4.12 Problem Set	99
Chapter 5 Conditionally Executing Instructions	103
5.1 The IF Instruction	103
5.2 The Conditions That Robots Can Test	104
5.2.1 Writing New Predicates	106
5.3 Simple Examples of the IF Instruction	108
5.3.1 The harvestOneRow Method	108
5.3.2 The faceNorthIfFacingSouth Method	109
5.3.3 The faceNorth Method	110
5.3.4 Determining the correctness of the IF Instruction	112
5.4 The IF/ELSE Instruction	113
5.5 Nested IF Instructions	115
5.6 More Complex Tests	119
5.7 When to Use an IF Instruction	121
5.8 Transformations for Simplifying IF Instructions	123
5.9 Polymorphism Revisited	127
5.10 Important Ideas From This Chapter	129
5.11 Problem Set	129
Chapter 6 Instructions That Repeat	136
6.1 The FOR-LOOP Instruction	136
6.2 The WHILE Instruction	139
6.2.1 Why WHILE is Needed	139
6.2.2 The Form of the WHILE Instruction	139
6.2.3 Building a WHILE Loop - the Four Step Process	140
6.2.4 A More Interesting Problem	142
6.3 Errors to Avoid with WHILE Loops	144
6.3.1 The Fence Post Problem	145
6.3.2 Infinite Execution	146
6.3.3 When the test of a WHILE is Checked	147
6.4 Nested WHILE Loops	148
6.4.1 A Good Example of Nesting	148
6.4.2 A Bad Example of Nesting	151
6.5 WHILE and IF Instructions	157
6.6 Reasoning about Loops	158
6.7 A Large Program Written by Stepwise Refinement	161
6.8 Enumerations and the While Statement	166
6.9 When to Use a Repeating Instruction	167
6.10 Important Ideas From This Chapter	169
6.11 Problem Set	169
Chapter 7 Advanced Techniques for Robots	184
7.1 Introduction to Recursion	184
7.2 More on Recursion	186
7.3 Tail Recursion and Looping	190
7.4 Going Formal	191
7.5 Searching	191
7.6 Doing Arithmetic	196
7.7 Polymorphism--Why Write Many Programs When One Will Do?	201
7.8 Conclusion	203
7.9 Important Ideas From This Chapter	204
7.10 Problem Set	204
Chapter 8 Concurrent Robot Programs	209
8.1 Simple Concurrent Programs	209
8.2 Robot Runs In Its Own Thread	210
8.3 Cooperation	211
8.4 Race Conditions	212
8.5 Deadlock	213
8.6 Important Ideas From This Chapter	215
8.7 Problem Set	215
Appendix	217
1 Java main	217
2 KarelRunner	218
3 Compiling and Executing Robot Code	219
4 Constructors in Java	220
5 Controllers and Inner Classes	221
6 Java Cloning	225
Index of Terms	227
Index of Classes Used in the Book	228
Index of Methods Used in the Book	229