Java · Theory

Java Statement Interface

Theory

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Java Statement Interface

Statement Interface sits in JDBC — Java talking to a database with SQL. Five steps: driver → Connection → Statement/PreparedStatement → ResultSet → close (try-with-resources).

For Statement Interface — prefer PreparedStatement. Never paste user input into SQL with +. That is SQL injection.

Statement Interface session: connection URL, user, and password. ResultSet is read row by row with next(). Close everything when done.

Let's take this on the board with one tiny Main class — no extra files. Output: Asha scored 72 then Pass. Real Main. Swap marks/name to show one idea from Java Statement Interface. Start from main, go line by line, and stop at each print. That output is the proof for Statement Interface.

Exam tip

Explain Java Statement Interface as: definition → why → one code idea.

Example

// Java
public class Main {
  public static void main(String[] args) {
    int marks = 72;
    String name = "Asha";
    System.out.println(name + " scored " + marks);
    if (marks >= 40) System.out.println("Pass");
  }
}

Output: Asha scored 72 then Pass. Real Main. Swap marks/name to show one idea from Java Statement Interface.

Short notes

DefStatement Interface — JDBC = Java API to talk to a database with SQL.
FlowStatement Interface — driver → Connection → Statement → ResultSet → close.
RuleStatement Interface — prefer PreparedStatement. Use try-with-resources.
TrapStatement Interface — string-concatenating user input into SQL.

// Java public class Main { public static void main(String[] args) { int marks = 72; String name = "Asha"; System.out.println(name + " scored " + marks); if (marks >= 40) System.out.println("Pass"); } }

Java Statement Interface

Example

Short notes

Questions

Java Statement Interface

Example

Short notes

Questions