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OCA/OCP Java SE 7 Programmer I & II Study Guide (Exams 1Z0-803 & 1Z0-804)

by Kathy Sierra, Bert Bates

October 2014

Intermediate to advanced

888 pages

26h 13m

English

McGraw Hill Computing

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Java RefresherIdentifiers and Keywords (OCA Objectives 1.2 and 2.1)Legal IdentifiersOracle’s Java Code ConventionsDefine Classes (OCA Objectives 1.2, 1.3, 1.4, 6.6, and 7.6)Source File Declaration RulesUsing the javac and java CommandsUsing public static void main(String[ ] args)Import Statements and the Java APIStatic Import StatementsClass Declarations and ModifiersExercise 1-1: Creating an Abstract Superclass and Concrete SubclassUse Interfaces (OCA Objective 7.6)Declaring an InterfaceDeclaring Interface ConstantsDeclare Class Members (OCA Objectives 2.1, 2.2, 2.3, 2.4, 2.5, 4.1, 4.2, 6.2, and 6.6)Access ModifiersNonaccess Member ModifiersConstructor DeclarationsVariable DeclarationsDeclare and Use enums (OCA Objective 1.2 and OCP Objective 2.5)Declaring enumsTwo-Minute DrillQ&A Self TestSelf Test Answers
Encapsulation (OCA Objectives 6.1 and 6.7)Inheritance and Polymorphism (OCA Objectives 7.1, 7.2, and 7.3)IS-AHAS-APolymorphism (OCA Objectives 7.2 and 7.3)Overriding / Overloading (OCA Objectives 6.1, 6.3, 7.2, and 7.3)Overridden MethodsOverloaded MethodsCasting (OCA Objectives 7.3 and 7.4)Implementing an Interface (OCA Objective 7.6)Legal Return Types (OCA Objectives 2.2, 2.5, 6.1, and 6.3)Return Type DeclarationsReturning a ValueConstructors and Instantiation (OCA Objectives 6.4, 6.5, and 7.5)Determine Whether a Default Constructor Will Be CreatedOverloaded ConstructorsInitialization BlocksStatics (OCA Objective 6.2)Static Variables and MethodsTwo-Minute DrillQ&A Self TestSelf Test Answers
Stack and Heap—Quick ReviewLiterals, Assignments, and Variables (OCA Objectives 2.1, 2.2, 2.3, and Upgrade Objective 1.2)Literal Values for All Primitive TypesAssignment OperatorsExercise 3-1: Casting PrimitivesScope (OCA Objectives 1.1 and 2.5)Variable Initialization (OCA Objective 2.1)Using a Variable or Array Element That Is Uninitialized and UnassignedLocal (Stack, Automatic) Primitives and ObjectsPassing Variables into Methods (OCA Objective 6.8)Passing Object Reference VariablesDoes Java Use Pass-By-Value Semantics?Passing Primitive VariablesGarbage Collection (OCA Objective 2.4)Overview of Memory Management and Garbage CollectionOverview of Java’s Garbage CollectorWriting Code That Explicitly Makes Objects Eligible for CollectionExercise 3-2: Garbage Collection ExperimentTwo-Minute DrillQ&A Self TestSelf Test Answers
Java Operators (OCA Objectives 3.1, 3.2, and 3.3)Assignment OperatorsRelational Operatorsinstanceof ComparisonArithmetic OperatorsConditional OperatorLogical OperatorsTwo-Minute DrillQ&A Self TestSelf Test Answers
Using String and StringBuilder (OCA Objectives 2.7 and 2.6)The String ClassImportant Facts About Strings and MemoryImportant Methods in the String ClassThe StringBuilder ClassImportant Methods in the StringBuilder ClassUsing Arrays (OCA Objectives 4.1 and 4.2)Declaring an ArrayConstructing an ArrayInitializing an ArrayUsing ArrayList (OCA Objective 4.3)When to Use ArrayListsArrayList Methods in ActionImportant Methods in the ArrayList ClassEncapsulation for Reference VariablesTwo-Minute DrillQ&A Self TestSelf Test Answers
Using if and switch Statements (OCA Objectives 3.4 and 3.5—also Upgrade Objective 1.1)if-else Branchingswitch Statements (OCA, OCP, and Upgrade Topic)Exercise 6-1: Creating a switch-case StatementCreating Loops Constructs (OCA Objectives 5.1, 5.2, 5.3, 5.4, and 5.5)Using while LoopsUsing do LoopsUsing for LoopsUsing break and continueUnlabeled StatementsLabeled StatementsExercise 6-2: Creating a Labeled while LoopHandling Exceptions (OCA Objectives 8.1, 8.2, 8.3, and 8.4)Catching an Exception Using try and catchUsing finallyPropagating Uncaught ExceptionsExercise 6-3: Propagating and Catching an ExceptionDefining ExceptionsException HierarchyHandling an Entire Class Hierarchy of ExceptionsException MatchingException Declaration and the Public InterfaceRethrowing the Same ExceptionExercise 6-4: Creating an ExceptionCommon Exceptions and Errors (OCA Objective 8.5)Where Exceptions Come FromJVM Thrown ExceptionsProgrammatically Thrown ExceptionsA Summary of the Exam’s Exceptions and ErrorsEnd of Part I—OCATwo-Minute DrillQ&A Self TestSelf Test Answers
Working with the Assertion Mechanism (OCP Objective 6.5)Assertions OverviewEnabling AssertionsUsing Assertions AppropriatelyWorking with Java 7 Exception Handling (OCP Objectives 6.2 and 6.3)Use the try Statement with multi-catch and finally ClausesAutocloseable Resources with a try-with-resources StatementTwo-Minute DrillQ&A Self TestSelf Test Answers
String, StringBuilder, and StringBuffer (OCP Objective 5.1)Dates, Numbers, Currencies, and Locales (OCP Objectives 12.1, 12.4, 12.5, and 12.6)Working with Dates, Numbers, and CurrenciesParsing, Tokenizing, and Formatting (OCP Objectives 5.1, 5.2, and 5.3)A Search TutorialLocating Data via Pattern MatchingTokenizingFormatting with printf() and format()Resource Bundles (OCP Objectives 12.2, 12.3, and 12.5)Resource BundlesProperty Resource BundlesJava Resource BundlesDefault LocaleChoosing the Right Resource BundleTwo-Minute DrillQ&A Self TestSelf Test Answers
File Navigation and I/O (OCP Objectives 7.1 and 7.2)Creating Files Using the File ClassUsing FileWriter and FileReaderCombining I/O ClassesWorking with Files and DirectoriesThe java.io.Console ClassFiles, Path, and Paths (OCP Objectives 8.1 and 8.2)Creating a PathCreating Files and DirectoriesCopying, Moving, and Deleting FilesRetrieving Information about a PathNormalizing a PathResolving a PathRelativizing a PathFile and Directory Attributes (OCP Objective 8.3)Reading and Writing Attributes the Easy WayTypes of Attribute InterfacesWorking with BasicFileAttributesWorking with DosFileAttributesWorking with PosixFileAttributesReviewing AttributesDirectoryStream (OCP Objective 8.4)FileVisitor (OCP Objective 8.4)PathMatcher (OCP Objective 8.5)WatchService (OCP Objective 8.6)Serialization (Objective 7.2)Two-Minute DrillQ&A Self TestSelf Test Answers
IS-A and HAS-A (OCP Objectives 3.3 and 3.4)Coupling and CohesionCouplingCohesionObject Composition Principles (OCP Objective 3.4)PolymorphismBenefits of CompositionSingleton Design Pattern (OCP Objective 3.5)What Is a Design Pattern?ProblemSolutionBenefitsDAO Design Pattern (OCP Objective 3.6)ProblemSolutionBenefitsFactory Design Pattern (OCP Objective 3.7)ProblemSolutionBenefitsTwo-Minute DrillQ&A Self TestSelf Test Answers
toString(), hashCode(), and equals() (OCP Objectives 4.7 and 4.8)The toString() MethodOverriding equals()Overriding hashCode()Collections Overview (OCP Objectives 4.5 and 4.6)So What Do You Do with a Collection?Key Interfaces and Classes of the Collections FrameworkList InterfaceSet InterfaceMap InterfaceQueue InterfaceUsing Collections (OCP Objectives 4.2, 4.4, 4.5, 4.6, 4.7, and 4.8)ArrayList BasicsAutoboxing with CollectionsThe Java 7 “Diamond” SyntaxSorting Collections and ArraysNavigating (Searching) TreeSets and TreeMapsOther Navigation MethodsBacked CollectionsUsing the PriorityQueue Class and the Deque InterfaceMethod Overview for Arrays and CollectionsMethod Overview for List, Set, Map, and QueueGeneric Types (OCP Objectives 4.1 and 4.3)The Legacy Way to Do CollectionsGenerics and Legacy CodeMixing Generic and Nongeneric CollectionsPolymorphism and GenericsGeneric MethodsGeneric DeclarationsTwo-Minute DrillQ&A Self TestSelf Test Answers
Nested Classes (OCP Objective 2.4)Inner ClassesCoding a “Regular” Inner ClassReferencing the Inner or Outer Instance from Within the Inner ClassMethod-Local Inner ClassesWhat a Method-Local Inner Object Can and Can’t DoAnonymous Inner ClassesPlain-Old Anonymous Inner Classes, Flavor OnePlain-Old Anonymous Inner Classes, Flavor TwoArgument-Defined Anonymous Inner ClassesStatic Nested ClassesInstantiating and Using Static Nested ClassesTwo-Minute DrillQ&A Self TestSelf Test Answers
Defining, Instantiating, and Starting Threads (OCP Objective 10.1)Defining a ThreadInstantiating a ThreadStarting a ThreadThread States and Transitions (OCP Objective 10.2)Thread StatesPreventing Thread ExecutionSleepingExercise 13-1: Creating a Thread and Putting It to SleepThread Priorities and yield( )Synchronizing Code, Thread Problems (OCP Objectives 10.3 and 10.4)Synchronization and LocksExercise 13-2: Synchronizing a Block of CodeThread DeadlockThread Interaction (OCP Objectives 10.3 and 10.4)Using notifyAll( ) When Many Threads May Be WaitingTwo-Minute DrillQ&A Self TestSelf Test AnswersExercise Answers
Concurrency with the java.util.concurrent PackageApply Atomic Variables and Locks (OCP Objective 11.2)Atomic VariablesLocksUse java.util.concurrent Collections (OCP Objective 11.1) and Use a Deque (OCP Objective 4.5)Copy-on-Write CollectionsConcurrent CollectionsBlocking QueuesUse Executors and ThreadPools (OCP Objective 11.3)Identifying Parallel TasksHow Many Threads Can You Run?CPU-Intensive vs. I/O-Intensive TasksFighting for a TurnDecoupling Tasks from ThreadsUse the Parallel Fork/Join Framework (OCP Objective 11.4)Divide and ConquerForkJoinPoolForkJoinTaskTwo-Minute DrillQ&A Self TestSelf Test Answers
Starting Out: Introduction to Databases and JDBCTalking to a DatabaseBob’s Books, Our Test DatabaseCore Interfaces of the JDBC API (OCP Objective 9.1)Connect to a Database Using DriverManager (OCP Objective 9.2)The DriverManager ClassThe JDBC URLJDBC Driver Implementation VersionsSubmit Queries and Read Results from the Database (OCP Objective 9.3)All of Bob’s CustomersStatementsResultSetsUpdating ResultSets (Not on the Exam!)When Things Go Wrong—Exceptions and WarningsUse PreparedStatement and CallableStatement Objects (OCP Objective 9.6)PreparedStatementCallableStatementConstruct and Use RowSet Objects (OCP Objective 9.5)Working with RowSetsJDBC Transactions (OCP Objective 9.4)JDBC Transaction ConceptsStarting a Transaction Context in JDBCRolling Back a TransactionUsing Savepoints with JDBCTwo-Minute DrillQ&A Self TestSelf Test Answers

Content preview from OCA/OCP Java SE 7 Programmer I & II Study Guide (Exams 1Z0-803 & 1Z0-804)

4 Operators

CERTIFICATION OBJECTIVE

• Using Java Operators

• Use Parentheses to Override Operator Precedence

• Test Equality Between Strings and Other Objects Using == and equals()

Two-Minute Drill

Q&A Self Test

If you’ve got variables, you’re going to modify them. You’ll increment them, add them together, and compare one to another (in about a dozen different ways). In this chapter, you’ll learn how to do all that in Java. For an added bonus, you’ll learn how to do things that you’ll probably never use in the real world, but that will almost certainly be on the exam.