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Can I execute a query to call a stored procedure with parameters in JDBC with out having to pass the parameters externally

for example, let's say I have a procedure named delete_all_rows_from_table, Can I execute the below query using JDBC
String query = "EXECUTE delete_all_rows_from_table('all')";
or must I do it in the below format?
String query = "{call delete_all_rows_from_table(?)}";
CallableStatement statement = connection.prepareCall(query);
statement.setString(1, "all");
statement.execute();
it is important because I want to implement a controller that takes in a stored procedure as string and excecutes it automtically, and in that case I wouldn't know the paremeters that will be coming. hence my question

method Name execute This statement does not declare an OUT parameter. Use { ?= call ... } to declare one

I had migrated database from Oracle to AWS Aurora PostgreSQL. I saw that all the packages are migrated as Function in PostgreSQL. I used AWS SCT for the Oracle schema conversion to postgreSQL. Java is the application middleware.
for example,
A package and associated stored proc in Oracle pk_audit.sp_get_audit converted to postgreSQL as pk_audit$sp_get_audit with a $ symbol.
When I run the web application, I'm getting an error like method Name execute This statement does not declare an OUT parameter. Use { ?= call ... } to declare one .
I don't have access to the application, but App team provided weblogic log. It says,
Method Name execute org.postgresql.util.PSQLException:
This statement does not declare an OUT parameter.Use { ?= call ... } to declare one.
org.postgresql.jdbc.PgCallableStatement.registerOutParameter(PgCallableStatement.java:205) weblogic.jdbc.wrapper.CallableStatement_org_postgresql_jdbc_PgCallableStatement.registerOutParameter(Unknown Source
package name specified in the Java code is pk_audit.sp_get_audit
Renamed the Postgres function pk_audit$sp_get_audit to pk_audit.sp_get_audit still facing the issue.
Is there anything I need to do in PostgreSQL DB ?
I need advise and help,Thanks.

As documented in CallableStatement, the JDBC syntax for calling stored procedures is one of these
{call ProcedureName(?, ...)}
{? = call FunctionName(?, ...)}
Any of the parameters can be OUT parameters. The return value is of course a type of OUT parameter.
So, if you had a stored procedure with 2 parameters and the second parameter was an OUT parameter, you would code it as:
String sql = "{call MyProcedure(?, ?)}";
try (CallableStatement stmt = conn.prepareCall(sql)) {
stmt.setInt(1, p1);
stmt.registerOutParameter(2, Types.VARCHAR);
...
}
If that same procedure is converted into a function, you would code it as:
String sql = "{? = call MyFunction(?)}";
try (CallableStatement stmt = conn.prepareCall(sql)) {
stmt.registerOutParameter(1, Types.VARCHAR);
stmt.setInt(2, p1);
...
}
If you cannot change the Java code making the call, you need to convert your functions back to procedures.

SQLException when executing a callablestatement

I am trying to call a Procedure from a package from my java application but receive an error. The code is set up like so...
------Java-----
Connection = conn;
String call_code="{? = call MY_PROCEDURE.Process_vale(?,?,?)}";
CallableStatement Process_cs=conn.prepareCall(call_code);
String bValue= "12345";
Process_cs.setString(1, bValue);
Process_cs.registerOutParameter(2, Types.INTEGER);
Process_cs.registerOutParameter(3, Types.VARCHAR);
Process_cs.execute();
The Procedure is setup like:
PROCEDURE Process_value (bValue VARCHAR2, PN_CD OUT NUMBER, PN_MSG OUT VARCHAR2).....
The Error I see is:
java.sql.SQLException: Missing IN or OUT parameter at index:: 4
I am curious as to why it mentions an index of 4, when the Procedure only has 3 parameters, I believe I am missing a critical fact here.

You have done some serious mistakes here. First Since you are calling a procedure you wont get any return value, only functions can have return values. So you have to call the procedure as follows.
String call_code="{call MY_PROCEDURE.Process_vale(?,?,?)}";
You could be successfully execute this if your procedure first parameter is IN type and other two parameters are OUT type.

Call PostgreSQL stored procedure with Java returns null

I have the following stored procedure written in PostgreSQL 9.3 that's working perfectly:
CREATE OR REPLACE FUNCTION getColor(i INT)
RETURNS VARCHAR AS $varColor$
DECLARE varColor varchar;
BEGIN
select color into varColor FROM colors where id = i;
return varColor;
END;
$varColor$ LANGUAGE plpgsql;
In fact, when I execute select getColor(2) in pgAdmin I get the expected value.
I am trying to call it like this from Java (simplified version):
String call = "{ call getColor(?,?) }";
CallableStatement cstmt = connection.prepareCall(call);
cstmt.setInt(1, 2);
cstmt.registerOutParameter(2, java.sql.Types.VARCHAR);
boolean hadResults = cstmt.execute();
The problem is that hadResults is always null.
Any ideas?

Postgresql stored procedures concept is something different than other vendors like Oracle.
Basically what in Oracle is called store procedure in Postgresql can be a function, and to call a function in Java is better to use prepare statements and executeQuery methods like in the following example
String call = "select getColor(?)";
PreparedStatement pstmt = connection.prepareStatement(call);
pstmt.setInt(1,1);
Resultset resultset = pstmt.executeQuery();
Thank you to all the guys who helped in the question comments!

Java CallableStatement registerOutParameter, what does it do?

I'm following a guide regarding callable statements.
In this guide, it says that I need to register the out parameter with the follow statement:
callsts.registerOutParameter(2, java.sql.Types.VARCHAR);
QUESTION: Why do I need to do this/what does it do ?
Complete Java code:
String getcall = "{call gettitle (?,?)}";
CallableStatement callsts = connect.prepareCall(getcall);
int nID = 15;
callsts.setInt(1, nID);
callsts.registerOutParameter(2, java.sql.Types.VARCHAR);
callsts.execute();
String calltitle = callsts.getString(2);
System.out.println("Callable Stamement Title: "+calltitle);
mySQL procedure:
DELIMITER $$
DROP PROCEDURE IF EXISTS `nothingtowear`.`gettitle` $$
CREATE PROCEDURE `nothingtowear`.`gettitle` (
IN nothingtowear_ID INT,
OUT nothingtowear_TITLE VARCHAR( 255 ))
BEGIN
SELECT Title INTO nothingtowear_TITLE
FROM articles
WHERE ID = nothingtowear_ID;
END $$
DELIMITER;

Out parameters are parameters passed to a SQL stored procedure that the procedure writes to.
In MySQL it can also be done via a SET command
SET out_param1 = value
See mysql stored-procedure: out parameter for another example
registerOutParameter will tell JDBC driver that it this is an otuput parameter and needs to be treated as such. E.g. it needs to use special syntax to call the procedure and retrieve output values after a statement is called

registerOutParameter is used to create a variable i.e. sql types on database server, so which is used to store value, and can get access using index in java calling stored procedures and functions context.
for example:
callableStatement.registerOutParameter(1, java.sql.Types.VARCHAR);
......
// get cursor and cast it to ResultSet
String var = callableStatement.getString(1);
In Oracle:
callableStatement.registerOutParameter(1, OracleTypes.CURSOR);
// get cursor and cast it to ResultSet
ResultSet rs = (ResultSet) callableStatement.getObject(1);