Java StringBuilder.insert() – Examples
In this tutorial, we will learn about the Java StringBuilder.insert() function, and learn how to use this function to insert a value/object in StringBuilder sequence, with the help of examples.
insert(int offset, boolean b)
StringBuilder.insert() inserts the string representation of the boolean argument into this StringBuilder sequence.
Syntax
The syntax of insert() function is
insert(int offset, boolean b)
where
| Parameter | Description |
|---|---|
| offset | The index at which insert operation happens in StringBuilder sequence. |
| b | This boolean value will be inserted at given offset. |
Returns
The function returns reference to this StringBuilder object.
Example 1 – insert(offset, b)
In this example, we will initialize a StringBuilder, and insert a boolean true value at offset 5.
Java Program
public class Example {
public static void main(String[] args) {
StringBuilder stringBuilder = new StringBuilder("abcdefghijk");
System.out.println("Before insert : " + stringBuilder.toString());
int offset = 5;
boolean b = true;
stringBuilder.insert(offset, b);
System.out.println("After insert : " + stringBuilder.toString());
}
} Output
Before insert : abcdefghijk After insert : abcdetruefghijk
insert(int offset, char c)
StringBuilder.insert() inserts the string representation of the char argument into this StringBuilder sequence.
Syntax
The syntax of insert() function is
insert(int offset, char c)
where
| Parameter | Description |
|---|---|
| offset | The index at which insert operation happens in StringBuilder sequence. |
| c | This char value will be inserted at given offset. |
Returns
The function returns reference to this StringBuilder object.
Example 2 – insert(offset, c)
In this example, we will initialize a StringBuilder, and insert a char 'M' value at offset 5.
Java Program
public class Example {
public static void main(String[] args) {
StringBuilder stringBuilder = new StringBuilder("abcdefghijk");
System.out.println("Before insert : " + stringBuilder.toString());
int offset = 5;
char c = 'M';
stringBuilder.insert(offset, c);
System.out.println("After insert : " + stringBuilder.toString());
}
} Output
Before insert : abcdefghijk After insert : abcdeMfghijk
insert(int offset, char[] str)
StringBuilder.insert() inserts the string representation of the char array argument into this StringBuilder sequence.
Syntax
The syntax of insert() function is
insert(int offset, char[] str)
where
| Parameter | Description |
|---|---|
| offset | The index at which insert operation happens in StringBuilder sequence. |
| str | This char array will be inserted at given offset. |
Returns
The function returns reference to this StringBuilder object.
Example 3 – insert(offset, str)
In this example, we will initialize a StringBuilder, and insert a char array str at offset 5.
Java Program
public class Example {
public static void main(String[] args) {
StringBuilder stringBuilder = new StringBuilder("abcdefghijk");
System.out.println("Before insert : " + stringBuilder.toString());
int offset = 5;
char[] str = {'X', 'Y', 'Z'};
stringBuilder.insert(offset, str);
System.out.println("After insert : " + stringBuilder.toString());
}
} Output
Before insert : abcdefghijk After insert : abcdeXYZfghijk
insert(int index, char[] str, int offset, int len)
StringBuilder.insert() inserts the string representation of a subarray of the str array argument into this StringBuilder sequence.
Syntax
The syntax of insert() function is
insert(int index, char[] str, int offset, int len)
where
| Parameter | Description |
|---|---|
| index | The position at which insert operation happens in StringBuilder sequence. |
| str | This char array value will be inserted at given index. |
| offset | Offset of subarray in str. |
| len | Length of subarray in str. |
Returns
The function returns reference to this StringBuilder object.
Example 4 – insert(index,str, offset, len)
In this example, we will initialize a StringBuilder, and insert a boolean true value at offset 5.
Java Program
public class Example {
public static void main(String[] args) {
StringBuilder stringBuilder = new StringBuilder("abcdefghijk");
System.out.println("Before insert : " + stringBuilder.toString());
int index = 5;
int offset = 2;
int len = 5;
char[] str = {'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H', 'I', 'J'};
stringBuilder.insert(index, str, offset, len);
System.out.println("After insert : " + stringBuilder.toString());
}
} Output
Before insert : abcdefghijk After insert : abcdeCDEFGfghijk
insert(int offset, double d)
StringBuilder.insert() inserts the string representation of the double argument into this StringBuilder sequence.
Syntax
The syntax of insert() function is
insert(int offset, double d)
where
| Parameter | Description |
|---|---|
| offset | The index at which insert operation happens in StringBuilder sequence. |
| d | This double value will be inserted at given offset. |
Returns
The function returns reference to this StringBuilder object.
Example 5 – insert(offset, d)
In this example, we will initialize a StringBuilder, and insert a double value at offset 5.
Java Program
public class Example {
public static void main(String[] args) {
StringBuilder stringBuilder = new StringBuilder("abcdefghijk");
System.out.println("Before insert : " + stringBuilder.toString());
int offset = 5;
double d = 3.14526985;
stringBuilder.insert(offset, d);
System.out.println("After insert : " + stringBuilder.toString());
}
} Output
Before insert : abcdefghijk After insert : abcde3.14526985fghijk
insert(int offset, float f)
StringBuilder.insert() inserts the string representation of the float argument into this StringBuilder sequence.
Syntax
The syntax of insert() function is
insert(int offset, float f)
where
| Parameter | Description |
|---|---|
| offset | The index at which insert operation happens in StringBuilder sequence. |
| f | This float value will be inserted at given offset. |
Returns
The function returns reference to this StringBuilder object.
Example 6 – insert(offset, f)
In this example, we will initialize a StringBuilder, and insert a float value at offset 5.
Java Program
public class Example {
public static void main(String[] args) {
StringBuilder stringBuilder = new StringBuilder("abcdefghijk");
System.out.println("Before insert : " + stringBuilder.toString());
int offset = 5;
float f = 3.14f;
stringBuilder.insert(offset, f);
System.out.println("After insert : " + stringBuilder.toString());
}
} Output
Before insert : abcdefghijk After insert : abcde3.14fghijk
insert(int offset, int i)
StringBuilder.insert() inserts the string representation of the second int argument into this StringBuilder sequence.
Syntax
The syntax of insert() function is
insert(int offset, int i)
where
| Parameter | Description |
|---|---|
| offset | The index at which insert operation happens in StringBuilder sequence. |
| i | This integer value will be inserted at given offset. |
Returns
The function returns reference to this StringBuilder object.
Example 7 – insert(offset, i)
In this example, we will initialize a StringBuilder, and insert a integer value at offset 5.
Java Program
public class Example {
public static void main(String[] args) {
StringBuilder stringBuilder = new StringBuilder("abcdefghijk");
System.out.println("Before insert : " + stringBuilder.toString());
int offset = 5;
int i = 44;
stringBuilder.insert(offset, i);
System.out.println("After insert : " + stringBuilder.toString());
}
} Output
Before insert : abcdefghijk After insert : abcde44fghijk
insert(int offset, long l)
StringBuilder.insert() inserts the string representation of the long argument into this StringBuilder sequence.
Syntax
The syntax of insert() function is
insert(int offset, long l)
where
| Parameter | Description |
|---|---|
| offset | The index at which insert operation happens in StringBuilder sequence. |
| l | This long value will be inserted at given offset. |
Returns
The function returns reference to this StringBuilder object.
Example 8 – insert(offset, l)
In this example, we will initialize a StringBuilder, and insert a long value at offset 5.
Java Program
public class Example {
public static void main(String[] args) {
StringBuilder stringBuilder = new StringBuilder("abcdefghijk");
System.out.println("Before insert : " + stringBuilder.toString());
int offset = 5;
long l = 444852489;
stringBuilder.insert(offset, l);
System.out.println("After insert : " + stringBuilder.toString());
}
} Output
Before insert : abcdefghijk After insert : abcde444852489fghijk
insert(int dstOffset, CharSequence s)
StringBuilder.insert() inserts the specified CharSequence into this StringBuilder sequence.
Syntax
The syntax of insert() function is
insert(int dstOffset, CharSequence s)
where
| Parameter | Description |
|---|---|
| dstOffset | The index at which insert operation happens in StringBuilder sequence. |
| s | This CharSequence will be inserted at given offset. |
Returns
The function returns reference to this StringBuilder object.
Example 9 – insert(dstOffset, s)
In this example, we will initialize a StringBuilder, and insert a char sequence XYZ at offset 5.
Java Program
public class Example {
public static void main(String[] args) {
StringBuilder stringBuilder = new StringBuilder("abcdefghijk");
System.out.println("Before insert : " + stringBuilder.toString());
int offset = 5;
CharSequence s = "XYZ";
stringBuilder.insert(offset, s);
System.out.println("After insert : " + stringBuilder.toString());
}
} Output
Before insert : abcdefghijk After insert : abcdeXYZfghijk
insert(int dstOffset, CharSequence s, int start, int end)
StringBuilder.insert() inserts a subsequence of the specified CharSequence into this StringBuilder sequence.
Syntax
The syntax of insert() function is
insert(int dstOffset, CharSequence s, int start, int end)
where
| Parameter | Description |
|---|---|
| dstOffset | The index at which insert operation happens in StringBuilder sequence. |
| s | This CharSequence value will be inserted at given offset. |
| start | The index at which subsequence starts in CharSequence s. |
| end | The index at which subsequence ends in CharSequence s. |
Returns
The function returns reference to this StringBuilder object.
Example 10 – insert(dstOffset, s, start, end)
In this example, we will initialize a StringBuilder, and insert a sub sequence from CharSequence s, at offset 5 of StringBuilder sequence. The subsequence in s begin at start and stop at end.
Java Program
public class Example {
public static void main(String[] args) {
StringBuilder stringBuilder = new StringBuilder("abcdefghijk");
System.out.println("Before insert : " + stringBuilder.toString());
int offset = 5;
int start = 2;
int end = 5;
CharSequence s = "XYZ123456";
stringBuilder.insert(offset, s, start, end);
System.out.println("After insert : " + stringBuilder.toString());
}
} Output
Before insert : abcdefghijk After insert : abcdeZ12fghijk
insert(int offset, Object obj)
StringBuilder.insert() inserts the string representation of the Object argument into this StringBuilder sequence.
Syntax
The syntax of insert() function is
insert(int offset, Object obj)
where
| Parameter | Description |
|---|---|
| offset | The index at which insert operation happens in StringBuilder sequence. |
| obj | This object’s string representation will be inserted at given offset. |
Returns
The function returns reference to this StringBuilder object.
Example 11 – insert(offset, obj)
In this example, we will initialize a StringBuilder, and insert an Object String value at offset 5. We will define a class Person and use its object to insert in StringBuilder sequence.
Java Program
public class Example {
public static void main(String[] args) {
StringBuilder stringBuilder = new StringBuilder("abcdefghijk");
System.out.println("Before insert : " + stringBuilder.toString());
int offset = 5;
Person obj = new Person("XYZ", 22);
stringBuilder.insert(offset, obj);
System.out.println("After insert : " + stringBuilder.toString());
}
}
class Person{
public String name;
int age;
public Person(String name, int age) {
this.name = name;
this.age = age;
}
public String toString() {
return '[' + name + '-' + age + ']';
}
} Output
Before insert : abcdefghijk After insert : abcde[XYZ-22]fghijk
insert(int offset, String str)
StringBuilder.insert() inserts the string into this StringBuilder sequence.
Syntax
The syntax of insert() function is
insert(int offset, String str)
where
| Parameter | Description |
|---|---|
| offset | The index at which insert operation happens in StringBuilder sequence. |
| str | The string we would like to insert in StringBuilder sequence. |
Returns
The function returns reference to this StringBuilder object.
Example 12 – insert(offset, str)
In this example, we will initialize a StringBuilder, and insert a string value "XYZ" at offset 5.
Java Program
public class Example {
public static void main(String[] args) {
StringBuilder stringBuilder = new StringBuilder("abcdefghijk");
System.out.println("Before insert : " + stringBuilder.toString());
int offset = 5;
String str = "XYZ";
stringBuilder.insert(offset, str);
System.out.println("After insert : " + stringBuilder.toString());
}
} Output
Before insert : abcdefghijk After insert : abcdeXYZfghijk
Conclusion
In this Java Tutorial, we have learnt the syntax of Java StringBuilder.insert() function, and also learnt how to use this function with the help of examples.