What is Parse/parsing? – Stack Overflow
In Java, What exactly is Parsing? Why are they used?
For example: rseInt(… ), and parsing a string?
asked Apr 24 ’09 at 22:03
You could say that parsing a string of characters is analyzing this string to find tokens, or items and then create a structure from the result.
In your example, calling rseInt on a string is parsing this string to find an integer.
So, if you have:
String someString = “123”;
And then you invoke:
int i = rseInt( someString);
You’re telling java to analyze the “123” string and find an integer there.
Other example:
One of the actions the java compiler does, when it compiles your source code is to “parse” your file and create tokens that match the java grammar.
When you fail to write the source code properly ( for instance forget to add a; at the end of a statement), it is the parser who identifies the error.
Here’s more information:
answered Apr 24 ’09 at 22:10
OscarRyzOscarRyz187k107 gold badges372 silver badges550 bronze badges
3
Parsing is to read the value of one object to convert it to another type. For example you may have a string with a value of “10”. Internally that string contains the Unicode characters ‘1’ and ‘0’ not the actual number 10. The method rseInt takes that string value and returns a real number.
String tenString = “10”
//This won’t work since you can’t add an integer and a string
Integer result = 20 + tenString;
//This will set result to 30
Integer result = 20 + rseInt(tenString);
answered Apr 24 ’09 at 22:07
Martin HarrisMartin Harris27. 3k7 gold badges86 silver badges96 bronze badges
2
From
Computers. to analyze (a string of
characters) in order to associate
groups of characters with the
syntactic units of the underlying
grammar.
The context of the definition is the translation of program text or a language in the general sense into its component parts with respect to a defined grammar — turning program text into code. In the context of a particular language keyword, though, it generally means to convert the string value of a fundamental data type into an internal representation of that data type. For example, the string “10” becomes the number (integer) 10.
answered Apr 24 ’09 at 22:06
tvanfossontvanfosson498k95 gold badges687 silver badges785 bronze badges
Parsing can be considered as a synonym of “Breaking down into small pieces” and then analysing what is there or using it in a modified way. In Java, Strings are parsed into Decimal, Octal, Binary, Hexadecimal, etc. It is done if your application is taking input from the user in the form of string but somewhere in your application you want to use that input in the form of an integer or of double type. It is not same as type casting. For type casting the types used should be compatible in order to caste but nothing such in parsing.
answered Nov 26 ’14 at 13:37
Sahil BabbarSahil Babbar5511 gold badge7 silver badges21 bronze badges
0
Parsing is just process of analyse the string of character and find the tokens from that string and parser is a component of interpreter and uses lexical analysis and then
syntactic parse it and then compile this code after this whole process of compilation.
answered Sep 27 ’12 at 16:10
1
Parsing means we are analyzing an object specifically. For example, when we enter some keywords in a search engine, they parse the keywords and give back results by searching for each word. So it is basically taking a string from the file and processing it to extract the information we want.
Example of parsing using indexOf to calculate the position of a string in another string:
String s=”What a Beautiful day! “;
int dexOf(“day”);//value of i would be 17
int dexOf(“be”);//value of j would be -1
int dexOf(“ea”);//value of k would be 8
paresInt essentially converts a String to a Integer.
String s=”9876543″;
int a=new Integer(s);//uses constructor
(“Constructor method: ” + a);
rseInt(s);//uses parseInt() method
(“parseInt() method: ” + a);
Output:
Constructor method: 9876543
parseInt() method: 9876543
NorthCat8, 63116 gold badges43 silver badges49 bronze badges
answered Jan 22 ’14 at 7:42
musicakcmusicakc4861 gold badge4 silver badges14 bronze badges
Parsing is the division of text in to a set of parts or tokens.
answered Aug 15 ’12 at 12:42
2
Parser – javatpoint
Parser is a compiler that is used to break the data into smaller elements coming from lexical analysis phase.
A parser takes input in the form of sequence of tokens and produces output in the form of parse tree.
Parsing is of two types: top down parsing and bottom up parsing.
Top down paring
The top down parsing is known as recursive parsing or predictive parsing.
Bottom up parsing is used to construct a parse tree for an input string.
In the top down parsing, the parsing starts from the start symbol and transform it into the input symbol.
Parse Tree representation of input string “acdb” is as follows:
Bottom up parsing
Bottom up parsing is also known as shift-reduce parsing.
In the bottom up parsing, the parsing starts with the input symbol and construct the parse tree up to the start symbol by tracing out the rightmost derivations of string in reverse.
Example
Production
Parse Tree representation of input string “id * id” is as follows:
Bottom up parsing is classified in to various parsing. These are as follows:
Shift-Reduce Parsing
Operator Precedence Parsing
Table Driven LR Parsing
LR( 1)
SLR( 1)
CLR ( 1)
LALR( 1)
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What is Parse? – Definition from Techopedia
What Does Parse Mean?
To parse, in computer science, is where a string of commands – usually a program – is separated into more easily processed components, which are analyzed for correct syntax and then attached to tags that define each component. The computer can then process each program chunk and transform it into machine language.
Techopedia Explains Parse
To parse is to break up a sentence or group of words into separate components, including the definition of each part’s function or form. The technical definition implies the same concept.
Parsing is used in all high-level programming languages. Languages like C++ and Java are parsed by their respective compilers before being transformed into executable machine code. Scripting languages, like PHP and Perl, are parsed by a web server, allowing the correct HTML to be sent to a browser.
Frequently Asked Questions about what does parsing mean in java
What does parsing do Java?
Parser is a compiler that is used to break the data into smaller elements coming from lexical analysis phase. A parser takes input in the form of sequence of tokens and produces output in the form of parse tree. Parsing is of two types: top down parsing and bottom up parsing.
What does parsing mean coding?
To parse, in computer science, is where a string of commands – usually a program – is separated into more easily processed components, which are analyzed for correct syntax and then attached to tags that define each component. The computer can then process each program chunk and transform it into machine language.Mar 23, 2017
What is string parsing?
Parsing String is the process of getting information that is needed in the String format. String parsing in java can be done by using a wrapper class. Using the Split method, a String can be converted to an array by passing the delimiter to the split method.