In this article, we will discuss StringBuilder’s capacity() method which returns the current capacity
1. StringBuilder’s capacity() method :
- This method returns current capacity of StringBuilder object
- Capacity is the amount of storage available to insert new characters
- Note: default capacity is 16
- Beyond capacity limit, a new allocation occurs based on below calculation
- Formula: New capacity = (old capacity * 2) + 2;
1.1 Method Signature:
public int capacity();
1.2 Returns:
- Returns current capacity
2. Examples on capacity() method:
StringBuilderCapacityMethod.java
package in.bench.resources.stringbuilder.methods;
public class StringBuilderCapacityMethod {
public static void main(String[] args) {
// 1. empty StringBuilder object
StringBuilder sb1 = new StringBuilder();
// capacity - default 16
System.out.println("1. Capacity of "
+ "EMPTY StringBuilder() : "
+ sb1.capacity());
// 2. empty StringBuilder object with single space
StringBuilder sb2 = new StringBuilder(" ");
// capacity - 16 + 1 = 17
System.out.println("2. Capacity of "
+ "StringBuilder(\" \") : "
+ sb2.capacity());
// 3. StringBuilder object with initialized string
StringBuilder sb3 = new StringBuilder("BenchResources");
// capacity - 16 + 14 = 30
System.out.println("3. Capacity of "
+ "StringBuilder(\"BenchResources\") : "
+ sb3.capacity());
// 4. StringBuilder object with initial capacity 65
StringBuilder sb4 = new StringBuilder(65);
// capacity - 55
System.out.println("4. Capacity of "
+ "StringBuilder(65) : "
+ sb4.capacity());
}
}
Output:
1. Capacity of EMPTY StringBuilder() : 16
2. Capacity of StringBuilder(" ") : 17
3. Capacity of StringBuilder("BenchResources") : 30
4. Capacity of StringBuilder(65) : 65
Related Articles :
- Java – StringBuilder class
- Java – StringBuilder append() method (13)
- Java – StringBuilder capacity() method
- Java – StringBuilder charAt(int index) method
- Java – StringBuilder delete(int start, int end) method
- Java – StringBuilder deleteCharAt(int index) method
- Java – StringBuilder ensureCapacity(int minimumCapacity) method
- Java – StringBuilder indexOf() method (2)
- Java – StringBuilder insert() method (12)
- Java – StringBuilder lastIndexOf() method (2)
- Java – StringBuilder length() method
- Java – StringBuilder replace(int start, int end, String str) method
- Java – StringBuilder reverse() method
- Java – StringBuilder substring(int start, int end) method
References :
- https://docs.oracle.com/javase/tutorial/essential/concurrency/immutable.html
- https://docs.oracle.com/javase/tutorial/essential/concurrency/imstrat.html
- https://docs.oracle.com/javase/tutorial/java/data/strings.html
- https://docs.oracle.com/javase/8/docs/api/java/lang/String.html
- https://docs.oracle.com/javase/8/docs/api/java/lang/class-use/String.html
- https://docs.oracle.com/javase/8/docs/api/java/lang/StringBuffer.html
- https://docs.oracle.com/javase/8/docs/api/java/lang/StringBuilder.html
Happy Coding !!
Happy Learning !!