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How to insert a value that contains an apostrophe (single quote) in postgresql from java insert?

I have data coming from html contact form which i am sending in a email through a java webservice. Everything is working fine but when user inserts data containing apostrophe (single quote) insert fails.
Pls help me to understand How and where to handle this data.
TIA

You just need to use Prepared Statements,it will escape special characters and avoid SQL_injection

You can use Prepared Statements, and you can just escape all special characters like single quote, double quote etc. before inserting in the database.

Can I escape escape sequences in MySQL string literals during scripts generating?

My pre-production task is to create tools to parse MySQL database schema and generate scripts to recreate it completely or partially. I've implemented first part of the task by fetching metadata from INFORMATION_SCHEMA tables and storing it in form of tree-like structure in memory. Now I'm busy generating scripts for each database objects. The issue I encountered is escaping Special Character Escape Sequences (as noted at this page, table 9.1) such as ' and " during writing string literals. Literals can be met in trigger and routine body or in SELECT part of view definition.
When I generate script for creating, say, trigger, literals with unescaped quotes corrupt the query and I cannot run it without manual correction. I get something like this.
Query with syntax error
I would like to be able to run my queries immediately after generating, so I need to write them with escaped quotes. I deviced two possible solution.
Fetch metadata of triggers, routines and views in the way that MySQL escape special sequences in literals. I've been browsing SO and docs for a while and yet to find an appropriate function on the MySQL side. (QUOTE() is not the case as it'll escape every escapable character in routine/trigger definition and even the ones that should not be escaped)
Escape that sequences manually just before script generating. I've tried to figure out the regexp to find and replace such units and here is what I got.
Pattern pattern = Pattern.compile("\'(.+)\'");
Matcher matcher = pattern.matcher("IF (NEW.AccountBalance <> 0 OR NEW.BlockedAmount <> 0) THEN SIGNAL SQLSTATE '45000' SET MESSAGE_TEXT='The account can't be closed!' END IF;");
StringBuilder sb = new StringBuilder();
while (matcher.find()) {
sb.append("'").append(matcher.group(1).replace("'", "\\\'")).append("'");
}
System.out.println(sb.toString());`
Certainly, this will not work if you've got several literals as I have in my example. It'll escape all single quotes between first and last single quote character and turn two or more literals into one senseless string. I'm guessing is it's possible at all to do it on the app side as regex cannot know where the literal starts and ends. Only me and MySQL can.
I've tried Walid's regexp solution from here and it escaped all target characters in my string, even starting and ending quotes for literals.
I'd highly appreciate any advice how to do it on the app or MySQL side.

Special character Symbol replacing ''�"

how to replace this symbol from java coding .. when i copied it into here its look like "�"
but in the coding it looks like a
small square box
if i saved the code its asking to save as 'utf-8' any one help me? Actually this is saved in the MYSQL Table while accession iam getting the problem
i will explain the scenario here..
I have to replace the single quotes and new line and double quotes
characters in a string in java..
when i was iterating, i found a string like 'RS approves President?s
Rule', i've checked in the database it is saved as 'RS approves
President[small square box]s Rule '....i first think that 'single
qoute' and tried to replace,
how can i replace this symbol..

Can you give more info on the flow of the string?
like:
input - webform
java - parses it or plain inserts it into the DB?
MySQL - stores the data
Make sure the input is set to (allow) UTF-8?
That the string in the Java is handled as UTF-8
Also that MySQL is set to UTF-8

Oracle parses text of "'{S}Paris2" as a string literal then finds {S} which it is treating as a SQL Escape Sequence which it doesn't recognize

I am getting the following error after running the jsp report.
Query Tag:doAfterBody(),0,Non supported SQL92 token at position: 3477: S
I know that the following snippet causing the problem ‘{S}’:
…….. AND (L.Applicable_Location_Region_ID IN (N'PARIS2', N'{S}Paris2'))
As per my investigation, I came to know following:
Oracle parses the SQL and treats the text of "'{S}Paris2" as a string literal then finds {S} which it is treating as a SQL Escape Sequence which it doesn't recognize.
The following link explains well about “Escape Characters”:
http://docs.oracle.com/cd/F49540_01/DOC/inter.815/a67843/cqspcl.htm
we must use {S} followed by name.
The above AND statement works fine with SQL Server and MySQL, but causes problem with Oracle as “When you use braces to escape a single character, the escaped character becomes a separate token in the query.”
Due to above reason the application treats {S}, as the escaped a single character with braces becomes a separate token in the query.
So please could you help me how can I escape single character with braces in oracle or any suggestion please.

Try
AND (L.Applicable_Location_Region_ID IN (N'PARIS2', N'\{S\}Paris2'))
EDIT:
Running this query from Toad
select (N'{S}test2') from dual where ((N'{S}test2') IN (N'test2', N'{S}test2'))
does work for me.
Are you sure that the problem is in Oracle database and not in the class/driver accessing it ?

Are escape sequences preserved in CLOB?

We are using Java and Oracle for development.
I have table in a oracle database which has a CLOB column in it. Some XYZ application dumps a text file in this column. The text file has multiple rows.
Is it possible that while reading the same CLOB file thru Java application, the escape sequences (new line chars, etc) may get lost??
Reason I asked this is, we gona parse this file line by line and if the escape sequences are lost, then we would be trouble. I would have done this analysis myself, but I am on vacation and my team needs urgent help.
Would really appreciate if you could provide any thoughts/inputs.

You need to ensure that you use the one correct and same character encoding throughout the whole process. I strongly recommend you to pickup UTF-8 for that. It covers every human character known at the world. Every step which involves handling of character data should be instructed to use the very same encoding.
In SQL context, ensure that the DB and table is created with UTF-8 charset. In JDBC context, ensure that JDBC driver is using UTF-8; this is often configureable by JDBC connection string. In Java code context, ensure that you're using UTF-8 when reading/writing character data from/to streams; you can specify it as 2nd constructor argument in InputStreamReader and OutputStreamWriter.

A CLOB stores character data. Carriage returns and line feeds are valid characters, though unprintable ones. As long as your XYZ app is correctly filling your CLOBs, the contents should be just as manageable to you as if they had come from the file.
Depending on the platform and the nature of said "XYZ app," lines could be separated by either \r(Mac), \r\n (DOS/Windows) or \n (Unix/Linux), and you should make allowance for this fact if necessary. This is one aspect where BufferedReader.readLine() is more convenient, as it transparently gets rid of this difference for you.

I'm not 100% sure what you mean by escape sequences in this context. Within a (for example) Java literal string, "\n" is an escape sequence representing a newline, but once that string is outputted into something (say, a database), it's not an escape sequence any more, it's an actual newline character.
Anyhow, to your direct question, Java through can read text from Oracle CLOBs perfectly fine. Newlines are not lost.