In this article, we will discuss StringBuffer’s insert() method which is used to insert specified argument at the specified offset (or say starting from specified index-position)
1. StringBuffer’s insert() method:
- This method is used to insert given argument to the buffer at the specified offset (or starting from specified index-position)
- before inserting, internally convert respective data-type into String format
- Note: There are 12 variants or overloaded insert() method, those are,
1.1 Method Signature:
public StringBuffer insert(int offset, boolean b);
public StringBuffer insert(int offset, char c);
public StringBuffer insert(int offset, char[] str);
public StringBuffer insert(int index, char[] str, int offset, int len);
public StringBuffer insert(int dstOffset, CharSequence s);
public StringBuffer insert(int dstOffset, CharSequence s, int start, int end);
public StringBuffer insert(int offset, double d);
public StringBuffer insert(int offset, float f);
public StringBuffer insert(int offset, int i);
public StringBuffer insert(int offset, long l);
public StringBuffer insert(int offset, Object obj);
public StringBuffer insert(int offset, String str);
1.2 Returns:
- Returns StringBuffer object after inserting given argument at the specified offset
- Argument can be any primitive data-types like boolean, char, int, long, float, double, etc.
- It can also be used to insert char[] array, CharSequence, Object or String
1.3 Throws:
- IndexOutOfBoundsException, if offset value passed invalid
- StringIndexOutOfBoundsException, if offset value passed invalid
2. Examples on insert() method:
2.1 To insert specified primitive boolean data-type
- Insert boolean-value to StringBuffer object at the specified offset or specified index-position
Method signature:
public StringBuilder insert(int offset, boolean b);
StringBufferInsertMethodForBoolean.java
package in.bench.resources.stringbuffer.methods;
public class StringBufferInsertMethodForBoolean {
public static void main(String[] args) {
// define boolean variable
boolean boolTest1 = true;
boolean boolTest2 = false;
// StringBuffer - 1
StringBuffer sb1 = new StringBuffer("BenchResources.Net");
// 1. A : before inserting -
// internally invokes toString() method
System.out.println("1.A Before inserting : " + sb1);
// insert at 18th index insert(offset, boolean) method
sb1.insert(18, boolTest1);
// 1. B : after inserting -
// internally invokes toString() method
System.out.println("1.B After inserting"
+ " at 18th postion : " + sb1);
// StringBuffer - 2
StringBuffer sb2 = new StringBuffer(" BenchResources.Net");
// 2. A : before inserting -
// internally invokes toString() method
System.out.println("\n\n2.A Before inserting : " + sb2);
// insert at 0th index insert(offset, boolean) method
sb2.insert(0, boolTest2);
// 2. B : after inserting -
// internally invokes toString() method
System.out.println("2.B After inserting"
+ " at 0th postion : " + sb2);
}
}
Output:
1.A Before inserting : BenchResources.Net
1.B After inserting at 18th postion : BenchResources.Nettrue
2.A Before inserting : BenchResources.Net
2.B After inserting at 0th postion : false BenchResources.Net
2.2 To insert specified primitive int data-type
- Insert int-value to StringBuffer object at the specified offset or index-position
Method signature:
public StringBuilder insert(int offset, int i);
StringBufferInsertMethodForInteger.java
package in.bench.resources.stringbuffer.methods;
public class StringBufferInsertMethodForInteger {
public static void main(String[] args) {
// define int variable
int iTest1 = 19;
int iTest2 = 333;
// StringBuffer - 1
StringBuffer sb1 = new StringBuffer("BenchResources.Net");
// 1. A : before inserting -
// internally invokes toString() method
System.out.println("1.A Before inserting : " + sb1);
// insert at 5th index using insert(offset, int) method
sb1.insert(5, iTest1);
// 1. B : after inserting -
// internally invokes toString() method
System.out.println("1.B After inserting"
+ " at 5th postion : " + sb1);
// StringBuffer - 2
StringBuffer sb2= new StringBuffer(" BenchResources.Net");
// 2. A : before inserting -
// internally invokes toString() method
System.out.println("\n\n2.A Before inserting : " + sb2);
// insert at 15th index using insert(offset, int) method
sb2.insert(15, iTest2);
// 2. B : after inserting -
// internally invokes toString() method
System.out.println("2.B After inserting"
+ " at 15th postion : " + sb2);
}
}
Output:
1.A Before inserting : BenchResources.Net
1.B After inserting at 5th postion : Bench19Resources.Net
2.A Before inserting : BenchResources.Net
2.B After inserting at 15th postion : BenchResources333.Net
2.3 To insert specified primitive long data-type
- Insert long-value to StringBuffer object at the specified offset or index-position
Method signature:
public StringBuffer insert(int offset, long l);
StringBufferInsertMethodForLong.java
package in.bench.resources.stringbuffer.methods;
public class StringBufferInsertMethodForLong {
public static void main(String[] args) {
// define long variable
long lngTest1 = 1912345;
long lngTest2 = 333444999;
// StringBuffer - 1
StringBuffer sb1 = new StringBuffer("BenchResources.Net");
// 1. A : before inserting -
// internally invokes toString() method
System.out.println("1.A Before inserting : " + sb1);
// insert at 5th index using insert(offset, long) method
sb1.insert(5, lngTest1);
// 1. B : after inserting -
// internally invokes toString() method
System.out.println("1.B After inserting"
+ " at 5th postion : " + sb1);
// StringBuffer - 2
StringBuffer sb2= new StringBuffer(" BenchResources.Net");
// 2. A : before inserting -
// internally invokes toString() method
System.out.println("\n\n2.A Before inserting : " + sb2);
// insert at 15th index using insert(offset, long) method
sb2.insert(15, lngTest2);
// 2. B : after inserting -
// internally invokes toString() method
System.out.println("2.B After inserting"
+ " at 15th postion : " + sb2);
}
}
Output:
1.A Before inserting : BenchResources.Net
1.B After inserting at 5th postion : Bench1912345Resources.Net
2.A Before inserting : BenchResources.Net
2.B After inserting at 15th postion : BenchResources333444999.Net
2.4 To insert specified primitive float data-type
- Insert float-value to StringBuffer object at the specified offset or index-position
Method signature:
public StringBuffer insert(int offset, float f);
StringBufferInsertMethodForFloat.java
package in.bench.resources.stringbuffer.methods;
public class StringBufferInsertMethodForFloat {
public static void main(String[] args) {
// define float variable
float ftTest1 = 19.23456f;
float ftTest2 = 258.589635f;
// StringBuffer - 1
StringBuffer sb1 =
new StringBuffer("Hello it's float value of ");
// 1. A : before inserting -
// internally invokes toString() method
System.out.println("1.A Before inserting : " + sb1);
// insert at 26th index using insert(offset, float) method
sb1.insert(sb1.length(), ftTest1);
// 1. B : after inserting -
// internally invokes toString() method
System.out.println("1.B After inserting"
+ " at 26th postion : " + sb1);
// StringBuffer - 2
StringBuffer sb2= new StringBuffer(" is a float value");
// 2. A : before inserting -
// internally invokes toString() method
System.out.println("\n\n2.A Before inserting : " + sb2);
// insert at 0th index using insert(offset, float) method
sb2.insert(0, ftTest2);
// 2. B : after inserting -
// internally invokes toString() method
System.out.println("2.B After inserting"
+ " at 0th postion : " + sb2);
}
}
Output:
1.A Before inserting :
Hello it's float value of
1.B After inserting at 26th postion :
Hello it's float value of 19.23456
2.A Before inserting :
is a float value
2.B After inserting at 0th postion :
258.58963 is a float value
2.5 To insert specified primitive double data-type
- Insert double-value to StringBuffer object at the specified offset or index-position
Method signature:
public StringBuffer insert(int offset, double d);
StringBufferInsertMethodForDouble.java
package in.bench.resources.stringbuffer.methods;
public class StringBufferInsertMethodForDouble {
public static void main(String[] args) {
// define double variable
double dblTest1 = 19.23456;
double dblTest2 = 258.589635;
// StringBuffer - 1
StringBuffer sb1 =
new StringBuffer("Hello it's double value of ");
// 1. A : before inserting -
// internally invokes toString() method
System.out.println("1.A Before inserting : " + sb1);
// insert at 26th index using insert(offset,double) method
sb1.insert(sb1.length(), dblTest1);
// 1. B : after inserting -
// internally invokes toString() method
System.out.println("1.B After inserting"
+ " at 26th postion : " + sb1);
// StringBuffer - 2
StringBuffer sb2 = new StringBuffer(" is a double value.");
// 2. A : before inserting -
// internally invokes toString() method
System.out.println("\n\n2.A Before inserting : " + sb2);
// insert at 0th index using insert(offset, double) method
sb2.insert(0, dblTest2);
// 2. B : after inserting -
// internally invokes toString() method
System.out.println("2.B After inserting"
+ " at 0th postion : " + sb2);
}
}
Output:
1.A Before inserting :
Hello it's double value of
1.B After inserting at 26th postion :
Hello it's double value of 19.23456
2.A Before inserting :
is a double value.
2.B After inserting at 0th postion :
258.589635 is a double value.
2.6 To insert specified primitive char data-type
- Insert char-value to StringBuffer object at the specified offset or index-position
Method signature:
public StringBuffer insert(int offset, char c);
StringBufferInsertMethodForChar.java
package in.bench.resources.stringbuffer.methods;
public class StringBufferInsertMethodForChar {
public static void main(String[] args) {
// define char variable
char chTest1 = 'A';
char chTest2 = 'b';
// StringBuffer - 1
StringBuffer sb1 =
new StringBuffer("The captial character is ");
// 1. A : before inserting -
// internally invokes toString() method
System.out.println("1.A Before inserting : " + sb1);
// insert at 25th index insert(offset, char) method
sb1.insert(25, chTest1);
// 1. B : after inserting -
// internally invokes toString() method
System.out.println("1.B After inserting"
+ " at 25th postion : " + sb1);
// StringBuffer - 2
StringBuffer sb2 =
new StringBuffer(" is a lower-case character.");
// 2. A : before inserting -
// internally invokes toString() method
System.out.println("\n\n2.A Before inserting : " + sb2);
// insert at 0th index insert(offset, char) method
sb2.insert(0, chTest2);
// 2. B : after inserting -
// internally invokes toString() method
System.out.println("2.B After inserting"
+ " at 0th postion : " + sb2);
}
}
Output:
1.A Before inserting : The captial character is
1.B After inserting at 25th postion : The captial character is A
2.A Before inserting : is a lower-case character.
2.B After inserting at 0th postion : b is a lower-case character.
2.7 To insert specified char[] array
- insert char-array[] to StringBuffer object at the specified offset or index-position
Method signature:
public StringBuffer insert(int offset, char[] str);
public StringBuffer insert(int index, char[] str, int offset, int len);
StringBufferInsertMethodForCharArray.java
package in.bench.resources.stringbuffer.methods;
public class StringBufferInsertMethodForCharArray {
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'};
// StringBuffer - 1
StringBuffer sb1 = new StringBuffer(
"Implicitly converted char[] to SB ");
// 1. A : before inserting -
// internally invokes toString() method
System.out.println("1.A Before inserting : " + sb1);
// insert at 34th index insert(offset, char[]) method
sb1.insert(sb1.length(), chArrayTest1);
// 1. B : after inserting -
// internally invokes toString() method
System.out.println("1.B After inserting"
+ " at 34th postion : " + sb1);
// StringBuffer - 2
StringBuffer sb2 = new StringBuffer(
" is a convreted SB from char[] array.");
// 2. A : before inserting -
// internally invokes toString() method
System.out.println("\n\n2.A Before inserting : " + sb2);
// insert at 0th index insert(offset, char[]) method
sb2.insert(0, chArrayTest2);
// 2. B : after inserting -
// internally invokes toString() method
System.out.println("2.B After inserting"
+ " at 0th postion : " + sb2);
}
}
Output:
1.A Before inserting :
Implicitly converted char[] to SB
1.B After inserting at 34th postion :
Implicitly converted char[] to SB Bench
2.A Before inserting :
is a convreted SB from char[] array.
2.B After inserting at 0th postion :
Resources is a convreted SB from char[] array.
2.8 To insert specified CharSequence
- Insert CharSequence to StringBuffer object at the specified offset or index-position
Method signature:
public StringBuffer insert(int dstOffset, CharSequence s);
public StringBuffer insert(int dstOffset, CharSequence s, int start, int end);
StringBufferInsertMethodForCharSequence.java
package in.bench.resources.stringbuffer.methods;
public class StringBufferInsertMethodForCharSequence {
public static void main(String[] args) {
// define CharSequence variable
CharSequence charSeq1 = "Bench";
CharSequence charSeq2 = "Resources.Net";
// StringBuffer - 1
StringBuffer sb1 = new StringBuffer("Resources.Net");
// 1. A : before inserting -
// internally invokes toString() method
System.out.println("1.A Before inserting : " + sb1);
// insert at 0th index insert(offset, CharSequence) method
sb1.insert(0, charSeq1);
// 1. B : after inserting -
// internally invokes toString() method
System.out.println("1.B After inserting"
+ " at 0th postion : " + sb1);
// StringBuffer - 2
StringBuffer sb2 = new StringBuffer("Bench");
// 2. A : before inserting -
// internally invokes toString() method
System.out.println("\n\n2.A Before inserting : " + sb2);
// insert at 5th index insert(offset, CharSequence) method
sb2.insert(sb2.length(), charSeq2);
// 2. B : after inserting -
// internally invokes toString() method
System.out.println("2.B After inserting"
+ " at 5th postion : " + sb2);
}
}
Output:
1.A Before inserting : Resources.Net
1.B After inserting at 0th postion : BenchResources.Net
2.A Before inserting : Bench
2.B After inserting at 5th postion : BenchResources.Net
2.9 To insert specified String object/value
- Insert String object/value to StringBuffer object at the specified offset or index-position
Method signature:
public StringBuffer insert(int offset, Object obj);
public StringBuffer insert(int offset, String str);
StringBufferInsertMethodForStringObject.java
package in.bench.resources.stringbuffer.methods;
public class StringBufferInsertMethodForStringObject {
public static void main(String[] args) {
// define String variable
String str1 = "Bench";
String str2 = "Tutorial.tut";
// StringBuffer - 1
StringBuffer sb1 = new StringBuffer("Resources.Net");
// 1. A : before inserting -
// internally invokes toString() method
System.out.println("1.A Before inserting : " + sb1);
// insert at 0th index insert(offset, CharSequence) method
sb1.insert(0, str1);
// 1. B : after inserting -
// internally invokes toString() method
System.out.println("1.B After inserting"
+ " at 0th postion : " + sb1);
// StringBuffer - 2
StringBuffer sb2 = new StringBuffer("Online");
// 2. A : before inserting -
// internally invokes toString() method
System.out.println("\n\n2.A Before inserting : " + sb2);
// insert at 6th index insert(offset, CharSequence) method
sb2.insert(sb2.length(), str2);
// 2. B : after inserting -
// internally invokes toString() method
System.out.println("2.B After inserting"
+ " at 6th postion : " + sb2);
}
}
Output:
1.A Before inserting : Resources.Net
1.B After inserting at 0th postion : BenchResources.Net
2.A Before inserting : Online
2.B After inserting at 6th postion : OnlineTutorial.tut
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 !!
