<< Chapter < Page Chapter >> Page >
Basic syntax errors in Java are explained.

Some errors are caused by violations of the syntax of Java. Although they are easy to understand, there is no easy way to find the exact causeof such errors except by checking the code around the location of the error character by character looking for the syntax error.

...expected

The syntax of Java is very specific about the required punctuation. This error occurs, for example, if you forget a semicolonat the end of a statement or don't balance parentheses:

if (i > j        // Error, unbalanced parentheses   max = i        // Error, missing semicolonelse   max = j;

Unfortunately, this syntax error is not necessarily caught precisely at the point of the mistake so you must carefully check the preceding characters inthe line or even in a previous line in order to find the problem.

Eclipse:
Syntax error, insert ") Statement" to complete IfStatement
Syntax error, insert ";" to complete Statement
Eclipse is more informative as to the precise syntax error encountered.

unclosed string literal

String literals must be enclosed in quotation marks. A literal is a source-code representation of a value; most literals are of primitive types like int or char , but there are also literals of type String and the literal null of any reference type. This error occurs if you fail to terminate the literal with quotation marks. Fortunately, the syntax of Javarequires that a string literal appear entirely on one line so the error message appears on the same line as the mistake. If you need a string literal that islonger than a single line, create two or more literals and concatenate them with + :

String longString =   "This is first half of a long string " +  "and this is the second half.";

Eclipse: String literal is not properly closed by a double-quote In Eclipse you can write a string literal of arbitrary length and the environment will break the string and insert the + automatically.

illegal start of expression

Most programming constructs are either statements or expressions. This error occurs when an expression is expected but not found. In Java, an assignment statement is considered to be an expression which returns a value , so errors concerning expressions also apply to assignment statements. The value of an assignment statement considered as an expressionis the value of the expression on the right-hand side that is assigned to the variable on the left-hand side. Examples:

  • An extra right parenthesis after the condition of an if -statement: if (i > j) )        // Error, extra parenthesis   max = i; Eclipse: Syntax error on token ")", delete this token The syntax of a programming language is defined in terms of tokens consisting of one or more characters. Identifiers and reserved keywords are tokens as are singlecharacters like + and sequences of characters like != . Eclipse diagnoses this as a simple syntax error and does not mention expressions.
  • Forgetting the right-hand side of an assignment statement: max = ;            // Error, missing right-hand side Eclipse: Syntax error on token "=", Expression expected after this token

Questions & Answers

where we get a research paper on Nano chemistry....?
Maira Reply
what are the products of Nano chemistry?
Maira Reply
There are lots of products of nano chemistry... Like nano coatings.....carbon fiber.. And lots of others..
learn
Even nanotechnology is pretty much all about chemistry... Its the chemistry on quantum or atomic level
learn
Google
da
no nanotechnology is also a part of physics and maths it requires angle formulas and some pressure regarding concepts
Bhagvanji
Preparation and Applications of Nanomaterial for Drug Delivery
Hafiz Reply
revolt
da
Application of nanotechnology in medicine
what is variations in raman spectra for nanomaterials
Jyoti Reply
I only see partial conversation and what's the question here!
Crow Reply
what about nanotechnology for water purification
RAW Reply
please someone correct me if I'm wrong but I think one can use nanoparticles, specially silver nanoparticles for water treatment.
Damian
yes that's correct
Professor
I think
Professor
Nasa has use it in the 60's, copper as water purification in the moon travel.
Alexandre
nanocopper obvius
Alexandre
what is the stm
Brian Reply
is there industrial application of fullrenes. What is the method to prepare fullrene on large scale.?
Rafiq
industrial application...? mmm I think on the medical side as drug carrier, but you should go deeper on your research, I may be wrong
Damian
How we are making nano material?
LITNING Reply
what is a peer
LITNING Reply
What is meant by 'nano scale'?
LITNING Reply
What is STMs full form?
LITNING
scanning tunneling microscope
Sahil
how nano science is used for hydrophobicity
Santosh
Do u think that Graphene and Fullrene fiber can be used to make Air Plane body structure the lightest and strongest. Rafiq
Rafiq
what is differents between GO and RGO?
Mahi
what is simplest way to understand the applications of nano robots used to detect the cancer affected cell of human body.? How this robot is carried to required site of body cell.? what will be the carrier material and how can be detected that correct delivery of drug is done Rafiq
Rafiq
if virus is killing to make ARTIFICIAL DNA OF GRAPHENE FOR KILLED THE VIRUS .THIS IS OUR ASSUMPTION
Anam
analytical skills graphene is prepared to kill any type viruses .
Anam
Any one who tell me about Preparation and application of Nanomaterial for drug Delivery
Hafiz
what is Nano technology ?
Bob Reply
write examples of Nano molecule?
Bob
The nanotechnology is as new science, to scale nanometric
brayan
nanotechnology is the study, desing, synthesis, manipulation and application of materials and functional systems through control of matter at nanoscale
Damian
Is there any normative that regulates the use of silver nanoparticles?
Damian Reply
what king of growth are you checking .?
Renato
What fields keep nano created devices from performing or assimulating ? Magnetic fields ? Are do they assimilate ?
Stoney Reply
why we need to study biomolecules, molecular biology in nanotechnology?
Adin Reply
?
Kyle
yes I'm doing my masters in nanotechnology, we are being studying all these domains as well..
Adin
why?
Adin
what school?
Kyle
biomolecules are e building blocks of every organics and inorganic materials.
Joe
how did you get the value of 2000N.What calculations are needed to arrive at it
Smarajit Reply
Privacy Information Security Software Version 1.1a
Good
Got questions? Join the online conversation and get instant answers!
Jobilize.com Reply

Get the best Algebra and trigonometry course in your pocket!





Source:  OpenStax, Compile and runtime errors in java. OpenStax CNX. Dec 28, 2009 Download for free at http://cnx.org/content/col10913/1.2
Google Play and the Google Play logo are trademarks of Google Inc.

Notification Switch

Would you like to follow the 'Compile and runtime errors in java' conversation and receive update notifications?

Ask