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Having Deleted a file in the folder that i was executing the javac seem to have fixed the problem.It was called String.java
and the content of the file were as mentioned under:Any help on why it happened or what the file was doing would be really appreciated.
The content of the file:-
""Java String Examples
The String class implements immutable character strings, which are read-only once the string object has been created and initialized. All string literals in Java programs, are implemented as instances of String class.
The easiest way to create a Java String object is using a string literal:
String str1 = "I can't be changed once created!";
A Java string literal is a reference to a String object. Since a String literal is a reference, it can be manipulated like any other String reference. i.e. it can be used to invoke methods of String class.
int myLenght = "Hello world".length();
The Java language provides special support for the string concatenation operator (+), which has been overloaded for Java Strings objects. String concatenation is implemented through the StringBuffer class and its append method.
String finalString = "Hello" + "World";
Would be executed as
String finalString = new StringBuffer().append("Hello").append("World").toString();
The Java compiler optimizes handling of string literals. Only one String object is shared by all strings having same character sequence. Such strings are said to be interned, meaning that they share a unique String object. The Java String class maintains a private pool where such strings are interned.
If(str1 == str2)
Would print Equal when executed.
Since the Java String objects are immutable, any operation performed on one String reference will never have any effect on other references denoting the same object.
String class provides various types of constructors to create String objects. Some of them are,
Creates a new String object whose content is empty i.e. "".
Creates a new String object whose content is same as the String object passed as an argument.
Note: Invoking String constructor creates a new string object, means it does not intern the String. Interned String object reference can be obtained by using intern() method of the String class.
String also provides constructors that take byte and char array as an argument and returns String object.
String equality - Compare Java String
String class overrides the equals() method of the Object class. It compares the content of the two string object and returns the boolean value accordingly.
String str3=new String("Hello") //Using constructor.
If(str1 == str2)
System.out.println("Not Equal 1");
If(str1 == str3)
System.out.println("I am constructed using constructor, hence not interned");
If( str1.equals(str3) )
System.out.println("Not Equal 3");
The output would be,
Not Equal 2
Note that == compares the references not the actual contents of the String object; Where as equals method compares actual contents of two String objects.
String class also provides another method equalsIgnoreCase() which ignores the case of contents while comparing.
Apart from these methods String class also provides compareTo methods.
int compareTo(String str2)
This method compares two Strings and returns an int value. It returns
- value 0, if this string is equal to the string argument
- a value less than 0, if this string is less than the string argument
- a value greater than 0, if this string is greater than the string argument
int compareTo(Object object)
This method behaves exactly like the first method if the argument object is actually a String object; otherwise, it throws a ClassCastException."""
Edited by: Gold_y on Oct 30, 2009 4:59 AM
what i wanted to know is what is wrong with the file??Why was the compiler acting up its just a normal file i created when i was looking for help material from internet for advancing my java Programming skills by copying the content of a webpage and compiler was working fine when i created it it just started acting up the next day.Also it was working just fine when i checked it in other folders which is why i came to the decision that it was some file that was causing the Problem and located the file by trial and error method removing 1 file at a time.
Edited by: Gold_y on Oct 30, 2009 10:34 PM
Edited by: Gold_y on Oct 31, 2009 1:29 AM
i may have agreed but it was throwing about 50 absolutely same errors every time i complied any program as long as they were in the same folder as that file even if it was Hello World program which i have been using ever since i started learning the ABC of java.I mean it was like the compiler had a urge to compile the Program like iron draws to a magnet.
Gold_y wrote:Probably every one of them was using "String".
i may have agreed but it was throwing about 50 absolutely same errors every time i complied any program as long as they were in the same folder as that file even if it was Hello World program which i have been using ever since i started learning the ABC of java. I mean it was like the compiler had a urge to compile the Program like iron draws to a magnet.
Because your code used a class called String and you had what appeared to be the source code of a Java String class, so it tried to compile that and went bananas. So don't do that: don't put things into .java files that aren't Java, and don't use names of standard classes for your own classes or files.