Java Language
- Getting started with Java Language
- Top 10 Java Errors with Solutions
- Awesome Book
- Awesome Community
- Awesome Course
- Awesome Tutorial
- Awesome YouTube
- 2D Graphics in Java
- Alternative Collections
- Annotations
- Apache Commons Lang
- AppDynamics and TIBCO BusinessWorks Instrumentation for Easy Integration
- Applets
- Arrays
- Asserting
- Atomic Types
- Audio
- Autoboxing
- Basic Control Structures
- Benchmarks
- BigDecimal
- BigInteger
- Bit Manipulation
- BufferedWriter
- ByteBuffer
- Bytecode Modification
- C++ Comparison
- Calendar and its Subclasses
- Character encoding
- Choosing Collections
- Class - Java Reflection
- Classes and Objects
- Classloaders
- Collection Factory Methods
- Collections
- Command line Argument Processing
- Common Java Pitfalls
- Comparable and Comparator
- CompletableFuture
- Concurrent Collections
- Concurrent Programming (Threads)
- Console I/O
- Constructors
- Converting to and from Strings
- Creating Images Programmatically
- Currency and Money
- Date Class
- Dates and Time (java.time.*)
- Default Methods
- Dequeue Interface
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- Documenting Java Code
- Dynamic Method Dispatch
- Encapsulation
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- Enum starting with number
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- EnumSet class
- Exceptions and exception handling
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- Expressions
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- FileUpload to AWS
- Fluent Interface
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- Functional Interfaces
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- Immutable Class
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- Inheritance
- InputStreams and OutputStreams
- Installing Java (Standard Edition)
- Interfaces
- Iterator and Iterable
- Java Agents
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- Java deployment
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- Java Floating Point Operations
- Java Memory Management
- Java Memory Model
- Java Native Access
- Java Native Interface
- Java Performance Tuning
- Java Pitfalls - Exception usage
- Java Pitfalls - Language syntax
- Java Pitfalls - Nulls and NullPointerException
- Java Pitfalls - Performance Issues
- Java Pitfalls - Threads and Concurrency
- Java plugin system implementations
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- Java Sockets
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- JavaBean
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- LinkedHashMap
- List vs SET
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- Local Inner Class
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- LocalTime
- log4j / log4j2
- Logging (java.util.logging)
- Maps
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- Nashorn JavaScript engine
- Nested and Inner Classes
- Networking
- New File I/O
- NIO - Networking
- Non-Access Modifiers
- NumberFormat
- Object Class Methods and Constructor
- Object Cloning
- Object References
- Operators
- Optional
- Oracle Official Code Standard
- Packages
- Parallel programming with Fork/Join framework
- Polymorphism
- Preferences
- Primitive Data Types
- Process
- Properties Class
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- Random Number Generation
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- Recursion
- Reference Data Types
- Reference Types
- Reflection API
- Regular Expressions
- Remote Method Invocation (RMI)
- Resources (on classpath)
- RSA Encryption
- Runtime Commands
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- Security & Cryptography
- Security & Cryptography
- SecurityManager
- Serialization
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- Sets
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- Splitting a string into fixed length parts
- Stack-Walking API
- Streams
- String Tokenizer
- StringBuffer
- StringBuilder
- Strings
- Adding toString() method for custom objects
- Case insensitive switch
- Changing the case of characters within a String
- Comparing Strings
- Counting occurrences of a substring or character in a string
- Finding a String Within Another String
- Getting the length of a String
- Getting the nth character in a String
- Joining Strings with a delimiter
- Platform independent new line separator
- Remove Whitespace from the Beginning and End of a String
- Replacing parts of Strings
- Reversing Strings
- Splitting Strings
- String concatenation and StringBuilders
- String pool and heap storage
- Substrings
- sun.misc.Unsafe
- super keyword
- The Classpath
- The Java Command - 'java' and 'javaw'
- The java.util.Objects Class
- ThreadLocal
- TreeMap and TreeSet
- Type Conversion
- Unit Testing
- Using Other Scripting Languages in Java
- Using the static keyword
- Using ThreadPoolExecutor in MultiThreaded applications.
- Varargs (Variable Argument)
- Visibility (controlling access to members of a class)
- WeakHashMap
- XJC
- XML Parsing using the JAXP APIs
- XML XPath Evaluation
- XOM - XML Object Model
Java Language Strings Getting the length of a String
Example
In order to get the length of a String object, call the length() method on it.
The length is equal to the number of UTF-16 code units (chars) in the string.
String str = "Hello, World!";
System.out.println(str.length()); // Prints out 13
A char in a String is UTF-16 value. Unicode codepoints whose values are ≥ 0x1000 (for example, most emojis) use two char positions. To count the number of Unicode codepoints in a String, regardless of whether each codepoint fits in a UTF-16 char value, you can use the codePointCount method:
int length = str.codePointCount(0, str.length());
You can also use a Stream of codepoints, as of Java 8:
int length = str.codePoints().count();
