In this article, we will discuss StringBuffer’s append() method which internally converts respective data-type into String format first and then append to buffer at the very end
1. StringBuffer’s append() method:
- This method is used to append given argument of any data-type to the buffer at the end
- Note: There are 13 variants or overloaded append() method, those are,
1.1 Method Signature:
public StringBuffer append(boolean b);
public StringBuffer append(char c);
public StringBuffer append(int i);
public StringBuffer append(long lng);
public StringBuffer append(float f);
public StringBuffer append(double d);
public StringBuffer append(char[] str);
public StringBuffer append(char[] str, int offset, int len);
public StringBuffer append(CharSequence s);
public StringBuffer append(CharSequence s, int start, int end);
public StringBuffer append(Object obj);
public StringBuffer append(String str);
public StringBuffer append(StringBuffer sb);
1.2 Returns:
- Returns StringBuffer object after appending given argument at the end of the buffer
- Argument can be any primitive data-types like boolean, char, int, long, float, double, etc.
- It can also be used to append char[] array, CharSequence, Object or String and StringBuffer
2. Examples on append() method:
2.1 To append specified primitive boolean data-type into StringBuffer object
Method signature:
public StringBuffer append(boolean b);
StringBufferAppendMethodForBoolean.java
package in.bench.resources.stringbuffer.methods;
public class StringBufferAppendMethodForBoolean {
public static void main(String[] args) {
// define boolean variable
boolean boolTest = true;
boolean boolTest2 = false;
// 1. appending boolean to StringBuffer
// using append(boolean) method
StringBuffer sb1 = new StringBuffer();
sb1.append(boolTest);
// 2. appending boolean to StringBuffer
// using append(boolean) method
StringBuffer sb2 = new StringBuffer();
sb2.append(boolTest2);
// print to console - internally invokes toString() method
System.out.println("1. Appending boolean TRUE "
+ "to StringBuffer : " + sb1);
System.out.println("2. Appending boolean FALSE "
+ "to StringBuffer : " + sb2);
}
}
Output:
1. Appending boolean TRUE to StringBuffer : true
2. Appending boolean FALSE to StringBuffer : false
2.2 To append specified primitive int data-type into StringBuffer object
Method signature:
public StringBuffer append(int i);
StringBufferAppendMethodForInteger.java
package in.bench.resources.stringbuffer.methods;
public class StringBufferAppendMethodForInteger {
public static void main(String[] args) {
// define int variable
int iTest1 = 19;
int iTest2 = 333;
// 1. appending int value to StringBuffer
// using append(int) method
StringBuffer sb1 = new StringBuffer();
sb1.append(iTest1);
// 2. appending int value to StringBuffer
// using append(int) method
StringBuffer sb2 = new StringBuffer();
sb2.append(iTest2);
// print to console - internally invokes toString() method
System.out.println("1. Appending int value "
+ "to StringBuffer : " + sb1);
System.out.println("2. Appending int value "
+ "to StringBuffer : " + sb2);
}
}
Output:
1. Appending int value to StringBuffer : 19
2. Appending int value to StringBuffer : 333
2.3 To append specified primitive long data-type into StringBuffer object
Method signature:
public StringBuffer append(long lng);
StringBufferAppendMethodForLong.java
package in.bench.resources.stringbuffer.methods;
public class StringBufferAppendMethodForLong {
public static void main(String[] args) {
// define int variable
long lngTest1 = 1912345;
long lngTest2 = 333444999;
// 1. appending long value to StringBuffer
// using append(long) method
StringBuffer sb1 = new StringBuffer();
sb1.append(lngTest1);
// 2. appending long value to StringBuffer
// using append(long) method
StringBuffer sb2 = new StringBuffer();
sb2.append(lngTest2);
// print to console - internally invokes toString() method
System.out.println("1. Appending long value "
+ "to StringBuffer : " + sb1);
System.out.println("2. Appending long value "
+ "to StringBuffer : " + sb2);
}
}
Output:
1. Appending long value to StringBuffer : 1912345
2. Appending long value to StringBuffer : 333444999
2.4 To append specified primitive float data-type into StringBuffer object
Method signature:
public StringBuffer append(float f);
StringBufferAppendMethodForFloat.java
package in.bench.resources.stringbuffer.methods;
public class StringBufferAppendMethodForFloat {
public static void main(String[] args) {
// define float variable
float ftTest1 = 19.23456f;
float ftTest2 = 258.589635f;
// 1. appending float value to StringBuffer
// using append(float) method
StringBuffer sb1 = new StringBuffer();
sb1.append(ftTest1);
// 2. appending float value to StringBuffer
// using append(float) method
StringBuffer sb2 = new StringBuffer();
sb2.append(ftTest2);
// print to console - internally invokes toString() method
System.out.println("1. Appending float value "
+ "to StringBuffer : " + sb1);
System.out.println("2. Appending float value "
+ "to StringBuffer : " + sb2);
}
}
Output:
1. Appending float value to StringBuffer : 19.23456
2. Appending float value to StringBuffer : 258.58963
2.5 To append specified primitive double data-type into StringBuffer object
Method signature:
public StringBuffer append(double d);
StringBufferAppendMethodForDouble.java
package in.bench.resources.stringbuffer.methods;
public class StringBufferAppendMethodForDouble {
public static void main(String[] args) {
// define double variable
double dblTest1 = 19.23456;
double dblTest2 = 258.589635;
// 1. appending double value to StringBuffer
// using append(double) method
StringBuffer sb1 = new StringBuffer();
sb1.append(dblTest1);
// 2. appending double value to StringBuffer
// using append(double) method
StringBuffer sb2 = new StringBuffer();
sb2.append(dblTest2);
// print to console - internally invokes toString() method
System.out.println("1. Appending double value "
+ "to StringBuffer : " + sb1);
System.out.println("2. Appending double value "
+ "to StringBuffer : " + sb2);
}
}
Output:
1. Appending double value to StringBuffer : 19.23456
2. Appending double value to StringBuffer : 258.589635
2.6 To append specified primitive char data-type into StringBuffer object
Method signature:
public StringBuffer append(char c);
StringBufferAppendMethodForChar.java
package in.bench.resources.stringbuffer.methods;
public class StringBufferAppendMethodForChar {
public static void main(String[] args) {
// define char variable
char chTest1 = 'A';
char chTest2 = 'b';
// 1. appending char value to StringBuffer
// using append(char) method
StringBuffer sb1 = new StringBuffer();
sb1.append(chTest1);
// 2. appending char value to StringBuffer
// using append(char) method
StringBuffer sb2 = new StringBuffer();
sb2.append(chTest2);
// print to console - internally invokes toString() method
System.out.println("1. Appending char value "
+ "to StringBuffer : " + sb1);
System.out.println("2. Appending char value "
+ "to StringBuffer : " + sb2);
}
}
Output:
1. Appending char value to StringBuffer : A
2. Appending char value to StringBuffer : b
2.7 To append specified char[] array into StringBuffer object
Method signature:
public StringBuffer append(char[] str);
public StringBuffer append(char[] str, int offset, int len);
StringBufferAppendMethodForCharArrays.java
package in.bench.resources.stringbuffer.methods;
public class StringBufferAppendMethodForCharArrays {
public static void main(String[] args) {
// define char[] variable
char[] chArrayTest1 = {'B', 'e', 'n', 'c', 'h'};
char[] chArrayTest2 = {'R', 'e',
's', 'o', 'u', 'r', 'c', 'e', 's'};
// 1. appending char[] value to StringBuffer
// using append(char[]) method
StringBuffer sb1 = new StringBuffer();
sb1.append(chArrayTest1);
// 2. appending char[] value to StringBuffer
// using append(char[]) method
StringBuffer sb2 = new StringBuffer();
sb2.append(chArrayTest2);
// print to console - internally invokes toString() method
System.out.println("1. Appending char[] value "
+ "to StringBuffer : " + sb1);
System.out.println("2. Appending char[] value "
+ "to StringBuffer : " + sb2);
}
}
Output:
1. Appending char[] value to StringBuffer : Bench
2. Appending char[] value to StringBuffer : Resources
2.8 To append specified CharSequence into StringBuffer object
Method signature:
public StringBuffer append(CharSequence s);
public StringBuffer append(CharSequence s, int start, int end);
StringBufferAppendMethodForCharSequence.java
package in.bench.resources.stringbuffer.methods;
public class StringBufferAppendMethodForCharSequence {
public static void main(String[] args) {
// define CharSequence variable
CharSequence charSeq1 = "Bench";
CharSequence charSeq2 = "Resources";
// 1. appending CharSequence value to StringBuffer
// using append(CharSequence) method
StringBuffer sb1 = new StringBuffer();
sb1.append(charSeq1);
// 2. appending CharSequence value to StringBuffer
// using append(CharSequence) method
StringBuffer sb2 = new StringBuffer();
sb2.append(charSeq2);
// print to console - internally invokes toString() method
System.out.println("1. Appending CharSequence value "
+ "to StringBuffer : " + sb1);
System.out.println("2. Appending CharSequence value "
+ "to StringBuffer : " + sb2);
}
}
Output:
1. Appending CharSequence value to StringBuffer : Bench
2. Appending CharSequence value to StringBuffer : Resources
2.9 To append specified String object into StringBuffer object
Method signature:
public StringBuffer append(Object obj);
public StringBuffer append(String str);
StringBufferAppendMethodForStringObject.java
package in.bench.resources.stringbuffer.methods;
public class StringBufferAppendMethodForStringObject {
public static void main(String[] args) {
// define String variable
String str1 = "Resources.Net";
String str2 = "Tutorial.tut";
// 1. appending String value to StringBuffer
// using append(String) method
StringBuffer sb1 = new StringBuffer("Bench");
sb1.append(str1);
// 2. appending String value to StringBuffer
// using append(String) method
StringBuffer sb2 = new StringBuffer("Online");
sb2.append(str2);
// print to console - internally invokes toString() method
System.out.println("1. Appending String value "
+ "to StringBuffer : " + sb1);
System.out.println("2. Appending String value "
+ "to StringBuffer : " + sb2);
}
}
Output:
1. Appending String value to StringBuffer : BenchResources.Net
2. Appending String value to StringBuffer : OnlineTutorial.tut
2.10 To append specified one StringBuffer object into another StringBuffer object
Method signature:
public StringBuffer append(StringBuffer sb);
StringBufferAppendMethod.java
package in.bench.resources.stringbuffer.methods;
public class StringBufferAppendMethod {
public static void main(String[] args) {
// 1. create StringBuffer object
StringBuffer sb1 = new StringBuffer(
"First StringBuffer object");
sb1.append(" created. ");
// 2. create another StringBuffer object
StringBuffer sb2 = new StringBuffer(
"Another StringBuffer object ");
sb2.append("to be appended.");
// appending StringBuffer value to another StringBuffer
// using append(StringBuffer) method
sb1.append(sb2);
// print to console - internally invokes toString() method
System.out.println("Appending 1-StringBuffer value "
+ "to 2-StringBuffer : \n\n" + sb1);
}
}
Output:
Appending 1-StringBuffer value to 2-StringBuffer :
First StringBuffer object created.
Another StringBuffer object to be appended.
Related Articles:
- Java – StringBuffer class
- Java – StringBuffer append() method (13)
- Java – StringBuffer capacity() method
- Java – StringBuffer charAt(int index) method
- Java – StringBuffer delete(int start, int end) method
- Java – StringBuffer deleteCharAt(int index) method
- Java – StringBuffer ensureCapacity(int minimumCapacity) method
- Java – StringBuffer indexOf() method (2)
- Java – StringBuffer insert() method (12)
- Java – StringBuffer lastIndexOf() method (2)
- Java – StringBuffer length() method
- Java – StringBuffer replace(int start, int end, String str) method
- Java – StringBuffer reverse() method
- Java – StringBuffer 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 !!