There are two ways to convert a String to boolean inward Java, first, past times using Boolean.parseBoolean() method together with second, past times using Boolean.valueOf() method.The parseBoolean() method returns an equivalent boolean value of given String, for example, if you lot move past times "true" it volition render the primitive boolean value true. Similarly, if you lot move past times "false" it volition render false. The skillful matter close this method is that it is instance insensitive, which agency if you lot move past times "true", "TRUE", or "True" you lot volition nonetheless acquire a true boolean value.
Another skillful matter close this method is that it doesn't throw an exception if you lot move past times whatsoever String value other than true together with false. For example, if you lot move past times "YES" it volition render false, which is non obvious but that's nonetheless meliorate than throwing an exception similar NumberFormatException.
The Boolean.valueOf() method operate similar, it returns a truthful boolean value for a non-null String equal to true, ignoring instance together with returns imitation for everything else. It every bit good returns a Boolean object instead of a primitive boolean value.
Also, both valueOf() together with parseBoolean() methods are aught safe, which agency they volition render imitation if you lot move past times aught i.e. parseBoolean(null) together with valueOf(null) volition render imitation instead of throwing NullPointerExcpeiton.
Btw, at that spot is unopen to other way to convert String to Boolean inward Java, past times using the constructor of Boolean bird e.g. new Boolean(String input) but I won't suggest you lot to purpose that because everytime you lot volition purpose this method it volition render a novel Boolean Object.
Instead, you lot should ever purpose valueOf() method because Boolean instances are immutable together with merely ii instances are plenty to comprehend all scenarios.
Even Joshua Bloch has advised using prefer static mill method similar valueOf() over constructor inward his classic Effective Java mass for surgical operation together with unloosen coupling. If you lot are interested, encounter the Item 1 on Effective Java tertiary Edition to acquire to a greater extent than close it.
Though inward the historic menses of auto-boxing, a Boolean tin easily hold upwards stored inward a boolean variable, this is an of import divergence which you lot should remember.
Another practise goodness of using the valueOf() method is that it caches the boolean value together with returns the already created Boolean.TRUE together with Boolean.FALSE value instead of creating a novel instance every time.
If you lot don't need a novel instance of the Boolean object hence you lot should ever purpose Boolean.valueOf() method to practise Boolean objects to acquire meliorate performance.
This method is every bit good overloaded to practise a Boolean object from both Strings every bit good every bit primitive boolean value e.g. both valueOf(true) together with valueOf("true") will render same Boolean.TRUE object. See The Complete Java Masterclass for to a greater extent than details.
In short:
1. Both parseBoolean() together with valueOf() are static methods defined inward java.lang.Boolean class.
2. The parseBoolean() returns a primitive boolean value piece valueOf() returns a Boolean object.
3. Both parseBoolean() together with valueOf() are null-safe which agency if you lot move past times aught String to them they volition render imitation boolean value instead of throwing NullPointerException.
4. Both methods are every bit good case-insensitive, which agency "true", "TRUE", together with "True" volition render same Boolean.TRUE value.
5. Prefer valueOf() over parseBoolean() if you lot need Boolean object because it returns cached Boolean objects, defined inward the Boolean bird itself i.e. Boolean.TRUE for truthful together with Boolean.FALSE for false.
6. The valueOf() provides meliorate surgical operation because of caching.
7. Autoboxing boolean primitive to Boolean object every bit good uses the Boolean.valueOf() method.
That's all close how to convert a String to boolean inward Java. You should purpose the Boolean.parseBoolean() method if you lot need a primitive boolean value together with Boolean.valueOf() if you lot need a Boolean object. The valueOf() method every bit good supply meliorate surgical operation because it ever returns the ii pre-created instance i.e. Boolean.TRUE together with Boolean.FALSE instead of creating a novel object everytime you lot parse a String to boolean.
Another skillful matter close this method is that it doesn't throw an exception if you lot move past times whatsoever String value other than true together with false. For example, if you lot move past times "YES" it volition render false, which is non obvious but that's nonetheless meliorate than throwing an exception similar NumberFormatException.
The Boolean.valueOf() method operate similar, it returns a truthful boolean value for a non-null String equal to true, ignoring instance together with returns imitation for everything else. It every bit good returns a Boolean object instead of a primitive boolean value.
Also, both valueOf() together with parseBoolean() methods are aught safe, which agency they volition render imitation if you lot move past times aught i.e. parseBoolean(null) together with valueOf(null) volition render imitation instead of throwing NullPointerExcpeiton.
1. Boolean.parseBoolean() Examples
// parseBoolean returns a boolean primitive value String value = "true"; boolean b = Boolean.parseBoolean(value); System.out.println(b); Output true
2. Boolean.valueOf() Examples
// valueOf returns a Boolean object String data = "false"; boolean f = Boolean.valueOf(data); System.out.println(f); Output false
Btw, at that spot is unopen to other way to convert String to Boolean inward Java, past times using the constructor of Boolean bird e.g. new Boolean(String input) but I won't suggest you lot to purpose that because everytime you lot volition purpose this method it volition render a novel Boolean Object.
Instead, you lot should ever purpose valueOf() method because Boolean instances are immutable together with merely ii instances are plenty to comprehend all scenarios.
Even Joshua Bloch has advised using prefer static mill method similar valueOf() over constructor inward his classic Effective Java mass for surgical operation together with unloosen coupling. If you lot are interested, encounter the Item 1 on Effective Java tertiary Edition to acquire to a greater extent than close it.
Difference betwixt parseBoolean together with valueOf() inward Java
Even though both methods tin hold upwards used to parse a String to a boolean value, at that spot is a slight divergence betwixt them. The parseBoolean() method returns a primitive boolean value piece the valueOf() returns a Boolean object.Though inward the historic menses of auto-boxing, a Boolean tin easily hold upwards stored inward a boolean variable, this is an of import divergence which you lot should remember.
Another practise goodness of using the valueOf() method is that it caches the boolean value together with returns the already created Boolean.TRUE together with Boolean.FALSE value instead of creating a novel instance every time.
If you lot don't need a novel instance of the Boolean object hence you lot should ever purpose Boolean.valueOf() method to practise Boolean objects to acquire meliorate performance.
This method is every bit good overloaded to practise a Boolean object from both Strings every bit good every bit primitive boolean value e.g. both valueOf(true) together with valueOf("true") will render same Boolean.TRUE object. See The Complete Java Masterclass for to a greater extent than details.
In short:
Java Program to Convert String to Boolean
Here is our consummate Java computer program to convert String to Boolean inward Java. It's quite similar to the before computer program for converting String to Integer, Long, Double, Float, Short, together with Byte inward Java. All of them follow same technique to convert String to other information types./** * * Influenza A virus subtype H5N1 elementary illustration to convert String to Boolean inward Java */ public class Hello { public static void main(String args[]) { // parseBoolean returns a boolean primitive value String value = "true"; boolean b = Boolean.parseBoolean(value); System.out.println(b); // valueOf returns a Boolean object String data = "false"; boolean f = Boolean.valueOf(data); System.out.println(f); value = "NO"; b = Boolean.parseBoolean(value); System.out.println(b); // aught String volition render false System.out.println(Boolean.parseBoolean(null)); System.out.println(Boolean.valueOf(null)); // whatsoever value other than truthful (Case-insensitive) will // render false System.out.println(Boolean.parseBoolean("YES")); System.out.println(Boolean.valueOf("Y")); } } Output true false false false false false false
Important Points
Some of import points close parseBoolean together with valueOf methods which are worth remembering:1. Both parseBoolean() together with valueOf() are static methods defined inward java.lang.Boolean class.
2. The parseBoolean() returns a primitive boolean value piece valueOf() returns a Boolean object.
3. Both parseBoolean() together with valueOf() are null-safe which agency if you lot move past times aught String to them they volition render imitation boolean value instead of throwing NullPointerException.
4. Both methods are every bit good case-insensitive, which agency "true", "TRUE", together with "True" volition render same Boolean.TRUE value.
5. Prefer valueOf() over parseBoolean() if you lot need Boolean object because it returns cached Boolean objects, defined inward the Boolean bird itself i.e. Boolean.TRUE for truthful together with Boolean.FALSE for false.
6. The valueOf() provides meliorate surgical operation because of caching.
7. Autoboxing boolean primitive to Boolean object every bit good uses the Boolean.valueOf() method.
That's all close how to convert a String to boolean inward Java. You should purpose the Boolean.parseBoolean() method if you lot need a primitive boolean value together with Boolean.valueOf() if you lot need a Boolean object. The valueOf() method every bit good supply meliorate surgical operation because it ever returns the ii pre-created instance i.e. Boolean.TRUE together with Boolean.FALSE instead of creating a novel object everytime you lot parse a String to boolean.
Further Learning
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