Hi, Can anyone help me on below queries? 1. What makes a class as "Thread safe class" ? 2. equals() method uses 3. Difference between String vs StringBuffer ?

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String objects are immutable in java while in StringBuffer objects u can make changes like insert ,delete or append characters
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String vs StringBuffer : 1) Mutability: String is immutable (Once created, cannot be modified) while StringBuffer is mutable (can be modified). 2) Performance: While performing concatenations you should prefer StringBuffer over String because it is faster. The reason is: When you concatenate strings...
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String vs StringBuffer : 1) Mutability: String is immutable (Once created, cannot be modified) while StringBuffer is mutable (can be modified). 2) Performance: While performing concatenations you should prefer StringBuffer over String because it is faster. The reason is: When you concatenate strings using String, you are actually creating new object every time since String is immutable. read less
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equals() method compares string to the specified object. The result is true if and only if the argument is not null and is a String object that represents the same sequence of characters as this object. public boolean equals(Object anObject)
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There are three ways to construct thread-safe Java class which has some state: 1. Make it truly immutable 2.Make field volatile. 3.Use a synchronized block
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If you are creating a library of classes that will be used in both thread-safe and non-thread-safe requirements, consider making wrappers an option. equals() method: This method compares this string to the specified object. The result is true if and only if the argument is not null and is a String...
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If you are creating a library of classes that will be used in both thread-safe and non-thread-safe requirements, consider making wrappers an option. equals() method: This method compares this string to the specified object. The result is true if and only if the argument is not null and is a String object that represents the same sequence of characters as this object. Syntax: public boolean equals(Object anObj) Parameters: anObj -- the object to compare this String against. Return Value : This method returns true if the String are equal; false otherwise. String vs StringBuffer: String is immutable whereas StringBuffer can change their values. String class is used to manipulate character strings that cannot be changed. Objects of type String are read only and immutable. The StringBuffer class is used to represent characters that can be modified. StringBuffer concatenation is significantly faster than String concatenation. read less
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to make a class thread safe, use synchronization process equals() method is used to compare two objects
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Strings are immutable and StringBuffer objects are mutable
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Core Java Advanced Java NET GATE Computer Science

equals method is in Object class whose default implementation checks the memory location of the objects which is similar to ===. The String class has overridden the equals method and new implementation checks the string content present in the object. One has to override the hashcode(in Object class)...
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equals method is in Object class whose default implementation checks the memory location of the objects which is similar to ===. The String class has overridden the equals method and new implementation checks the string content present in the object. One has to override the hashcode(in Object class) method too when override the equals method. read less
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Hi, Thread Safe Class: If your class is exposed to concurrent threads then you need to device a policy to prevent multiple threads to access the class properties at the same time. (1) you can use intrinsic synchronized() blocking. (2) you can make property volatile. (3) you can use Atomic class. Equal() it...
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Hi, Thread Safe Class: If your class is exposed to concurrent threads then you need to device a policy to prevent multiple threads to access the class properties at the same time. (1) you can use intrinsic synchronized() blocking. (2) you can make property volatile. (3) you can use Atomic class. Equal() it is used to equate the references whether they point to same objects or not, this method is defined by Object class, if you are overriding equal() method in your class then you also need to override hashcode() method. String vs StringBuffer String is immutable object, that means once object is created you cannot change it, it has no setter() method. StringBuffer() is a mutable object, you can change its content after the object is created, means it provides setter() methods Vijay read less
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1.By making all methods in a class as synchronized, a class can become thread safe. 2.equals() method is to compare the content of object , in String, Wrapper classes(Integer,Double,etc) the equals() is overridden. If its a custom class, you need override the equals() and provide the code inside to...
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1.By making all methods in a class as synchronized, a class can become thread safe. 2.equals() method is to compare the content of object , in String, Wrapper classes(Integer,Double,etc) the equals() is overridden. If its a custom class, you need override the equals() and provide the code inside to compare the custom object. 3.String is immutable(means u cant change the String value), StringBuffer is immutable. String is not synchronized, and StringBuffer is Synchronized. read less
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