Java

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• What Java is today ~20 min
• Where Java runs ~15 min
• JDK distributions and how to choose one ~20 min
• Install a JDK ~30 min
• Your first program ~30 min
• javac, java and the source launcher ~25 min
• Source to bytecode to the JVM ~25 min
• Try it in jshell ~20 min
• Reading your first error ~30 min

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• What an IDE does for you ~20 min
• Create and run a project ~30 min
• Code completion, navigation and refactoring ~25 min
• The debugger, first look: breakpoints and stepping ~30 min
• Choosing and switching JDKs ~30 min
• Git: save your work ~35 min
• Maven and Gradle: what a build tool is for ~35 min

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• Program structure ~35 min
• Variables, constants and var ~35 min
• Primitive types and literals ~35 min
• Reference types and null ~30 min
• Integer arithmetic ~35 min
• Floating-point arithmetic ~35 min
• Booleans, comparisons and logic ~35 min
• char and Unicode ~30 min
• Conversions and casting ~40 min
• Operators, precedence and scope ~40 min

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• Output and formatting ~40 min
• Console input ~45 min
• Command-line arguments ~35 min
• if and else ~40 min
• switch statements and switch expressions ~40 min
• while and do-while ~45 min
• for and enhanced for ~45 min
• break, continue and loop design ~60 min
• A first look at pattern-matching switch ~30 min

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• Strings are immutable objects ~25 min
• Searching, slicing, and transforming text ~40 min
• Comparing strings ~30 min
• Formatting and text blocks ~30 min
• StringBuilder ~30 min
• Arrays ~40 min
• Traversal patterns: count, sum, min/max, search ~40 min
• Sorting and binary search ~40 min
• Multidimensional arrays ~35 min
• Processing a small data file ~50 min

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• Defining and calling methods ~40 min
• Parameters and return values ~50 min
• Overloading and varargs ~45 min
• Scope and the call stack ~45 min
• Pass-by-value and references ~60 min
• Recursion ~55 min
• Decomposition and stepwise refinement ~50 min
• Designing and testing methods ~60 min

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• Classes, objects and references ~45 min
• Fields and methods: state and behavior ~45 min
• Constructors and this ~55 min
• Access modifiers and encapsulation ~50 min
• Validation and invariants ~50 min
• Getters, setters and when not to write them ~50 min
• static members ~50 min
• toString, equals and hashCode ~60 min
• Designing a class from a specification ~60 min

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• Inheritance, extends and super ~55 min
• Overriding and dynamic dispatch ~60 min
• Abstract classes ~45 min
• Interfaces ~55 min
• Default and static interface methods ~50 min
• Functional interfaces, first look ~45 min
• instanceof and type patterns ~50 min
• Composition versus inheritance: when to use which ~60 min

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• Enums with fields and behavior ~55 min
• Records ~55 min
• Immutability and value-oriented design ~55 min
• Sealed classes and interfaces ~50 min
• Record patterns and exhaustive switch ~60 min
• Data-transfer objects ~45 min
• Modeling a domain: from verbose Java to modern Java ~70 min

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• The collections framework ~50 min
• List and ArrayList ~55 min
• Sets and their three implementations ~55 min
• Maps from keys to values ~60 min
• Queues, deques and priority queues ~55 min
• Immutable and sequenced collections ~55 min
• Iteration and modification ~50 min
• Choosing a collection ~60 min
• Generic classes and methods ~55 min
• Bounds, wildcards and PECS ~60 min
• Type erasure ~50 min

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• Lambdas and functional interfaces ~50 min
• Method references ~45 min
• Predicate, Function, Consumer and Supplier ~55 min
• Stream pipelines ~60 min
• flatMap and reduce ~55 min
• Collectors, grouping and partitioning ~60 min
• Optional ~50 min
• Loops or streams? ~55 min

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• What an exception is ~45 min
• try, catch and finally ~55 min
• Checked and unchecked exceptions ~50 min
• throw, throws and propagation ~55 min
• Custom exceptions and wrapping ~55 min
• try-with-resources ~50 min
• Good error messages and a handling strategy ~55 min
• Debugging from a stack trace ~55 min

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• Path and Files ~50 min
• Reading and writing text files ~55 min
• Directories and walking a tree ~50 min
• Byte streams, character streams and buffering ~50 min
• Serialization concepts ~40 min
• JSON with Jackson ~60 min
• java.time: dates, times and instants ~55 min
• Time zones, formatting and parsing ~60 min

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• What a build tool actually does ~45 min
• The standard project layout ~40 min
• Maven and the pom.xml ~50 min
• The Maven lifecycle: compile, test, package ~50 min
• Dependencies, scopes and repositories ~55 min
• Transitive dependencies and version conflicts ~55 min
• Plugins and JAR creation ~55 min
• Gradle and the Kotlin DSL ~55 min

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• Why test ~45 min
• JUnit tests and assertions ~60 min
• Parameterized tests ~50 min
• Organizing tests ~55 min
• Test doubles and Mockito ~60 min
• Integration tests and Testcontainers ~55 min
• Code coverage ~50 min
• Formatting and static analysis ~50 min

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• Compiler errors, runtime exceptions and logic errors ~45 min
• The debugger in depth ~55 min
• Logging with SLF4J and Logback ~50 min
• Configuration and environment variables ~45 min
• .gitignore and a Git workflow ~50 min
• Branches, merges and pull requests ~55 min

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• Relational databases ~45 min
• SQL fundamentals ~70 min
• Connecting with JDBC ~55 min
• Prepared statements and result sets ~65 min
• Transactions ~55 min
• Connection pools ~40 min
• JPA, Jakarta Persistence and Hibernate ~65 min
• JDBC or ORM? ~35 min

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• Networking fundamentals ~45 min
• HTTP: URLs, methods, status codes and headers ~60 min
• REST and JSON APIs ~60 min
• HttpClient: synchronous requests ~60 min
• Asynchronous requests ~50 min
• Building an API client ~60 min
• Authentication concepts ~55 min

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• The Java backend landscape: Spring Boot and Jakarta EE ~45 min
• Dependency injection ~55 min
• Controllers and REST endpoints ~60 min
• Services and repositories ~55 min
• Configuration and profiles ~50 min
• Validation and error responses ~60 min
• Database integration with Spring Data ~65 min

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• Processes and threads ~35 min
• Creating threads and Runnable ~45 min
• Race conditions ~45 min
• synchronized, locks and volatile ~55 min
• Atomic variables and concurrent collections ~55 min
• Deadlock ~50 min
• Executors, thread pools and Future ~55 min
• CompletableFuture ~55 min
• Virtual threads ~55 min
• Structured concurrency and scoped values ~50 min

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• Bytecode and javap ~40 min
• Class loading and initialization ~40 min
• Stack, heap and references ~40 min
• Garbage collection ~45 min
• The JIT compiler ~40 min
• Boxing, allocation and common costs ~45 min
• Profiling with JDK Flight Recorder ~40 min
• Benchmarking with JMH ~50 min

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• Packages, imports, and package visibility ~40 min
• JAR files and manifests ~35 min
• The class path ~40 min
• Modules and module-info.java ~45 min
• The module path, and when modules are worth it ~40 min
• jlink and custom runtimes ~35 min
• jpackage and distributing an application ~40 min

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• DRY, KISS and separation of concerns ~50 min
• The SOLID principles ~60 min
• Composition, immutability and dependency inversion ~55 min
• Layered architecture ~55 min
• Creational patterns: factory and builder ~55 min
• Behavioral patterns: strategy and observer ~60 min
• Structural patterns: adapter and decorator ~60 min

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• Input validation ~60 min
• SQL injection ~55 min
• Authentication and authorization ~60 min
• Passwords and secrets ~65 min
• Secure HTTP and TLS ~50 min
• Dependency vulnerabilities ~55 min
• Deserialization risks ~55 min
• Modern Java practice and legacy code ~50 min

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• The project and its requirements ~45 min
• Designing the domain ~55 min
• Persistence and files ~55 min
• The HTTP API ~60 min
• Tests and logging ~50 min
• Build, package and document ~50 min
• Review against the checklist ~45 min