Checking in RefCursorInSample

Author: Nirmala Sundarappa

java/jdbc/AdvancedSamples/RefCursorInSample.java

@@ -0,0 +1,249 @@
+/* Copyright (c) 2018, Oracle and/or its affiliates. All rights reserved.*/
+
+/*
+ DESCRIPTION
+ 
+ REF CURSOR as INPUT parameter sample.
+ This capability was added in the JDBC thin driver in 18c.
+ To run the sample, you must enter the DB user's password from the 
+ console, and optionally specify the DB user and/or connect URL on 
+ the command-line. You can also modify these values in this file 
+ and recompile the code. 
+ java RefCursorInSample -l <url> -u <user> 
+ */
+
+import java.io.BufferedReader;
+import java.io.InputStreamReader;
+import java.sql.CallableStatement;
+import java.sql.Connection;
+import java.sql.ResultSet;
+import java.sql.SQLException;
+import java.sql.Statement;
+
+import oracle.jdbc.OracleTypes;
+import oracle.jdbc.pool.OracleDataSource;
+import oracle.jdbc.OracleCallableStatement;
+
+public class RefCursorInSample {
+ 
+ final static String DEFAULT_URL = "jdbc:oracle:thin:@//myhost:myport/myservice";
+ final static String DEFAULT_USER = "myuser";
+ final static String DEFAULT_PASSWORD = "mypassword";
+
+ // You must provide non-default values for all 3 parameters to execute the program
+ static String url = DEFAULT_URL;
+ static String user = DEFAULT_USER;
+ static String password = DEFAULT_PASSWORD;
+
+ // Connection object for REF CURSOR as INPUT parameter.
+ // The sample uses only one connection for all REF CURSOR
+ // operations in this demo program.
+ private Connection conn;
+ 
+ // Package name used in this sample
+ private final String PACKAGE_NAME = "REF_CURSOR_IN_JDBC_SAMPLE";
+
+ // Function names used in this sample
+ private final String FUNCTION_NAME1 = "GET_EMP_CURSOR";
+ private final String FUNCTION_NAME2 = "NAVIGATE_EMP_CURSOR";
+ 
+ 
+ /**
+ * Entry point of the sample.
+ * 
+ * @param args
+ * Command line arguments. Supported command line options: -l <url>
+ * -u <user>
+ * @throws Exception
+ */
+ public static void main(String args[]) throws Exception {
+ RefCursorInSample refCursorSample = new RefCursorInSample();
+
+ getRealUserPasswordUrl(args);
+
+ // Get a connection and initialize the schema.
+ refCursorSample.setup();
+ 
+ // Shows REF CURSOR IN with setCursor() call
+ refCursorSample.setCursorSample();
+
+ // Drop table and disconnect from the database.
+ refCursorSample.cleanup();
+ }
+ 
+ // Gets connection to the database and create a stored procedure.
+ void setup() throws SQLException {
+ conn = getConnection();
+ createFunctions();
+ }
+ 
+ // Drop the stored procedure and disconnect from the database
+ void cleanup() throws SQLException {
+ if (conn != null) {
+ dropFunctions();
+ conn.close();
+ conn = null;
+ }
+ }
+ 
+ // Shows how to use REF CURSOR IN with setCursor() call
+ void setCursorSample() throws SQLException {
+ 
+ show("======== setCursor Sample ========");
+ 
+ // Prepare a PL/SQL call to get a REF CURSOR as an output
+ try ( CallableStatement call1 =
+ conn.prepareCall ("{ ? = call " + PACKAGE_NAME + "." + FUNCTION_NAME1 + "() }")) {
+ call1.registerOutParameter (1, OracleTypes.CURSOR);
+ call1.execute ();
+ try (ResultSet rset = (ResultSet)call1.getObject (1) ) {
+ 
+ // Dump the first row from the cursor
+ show("Fetch first row of a ref cursor in Java:");
+ if(rset.next ())
+ show(rset.getString ("EMPNO") + " "
+ + rset.getString ("ENAME"));
+ 
+ // Prepare a PL/SQL call to set a REF CURSOR as an input
+ try ( CallableStatement call2 =
+ conn.prepareCall ("{ ? = call " + PACKAGE_NAME + "." + FUNCTION_NAME2 + "(?) }")) {
+ 
+ call2.registerOutParameter (1, OracleTypes.INTEGER);
+ ((OracleCallableStatement)call2).setCursor(2, rset);
+ call2.execute ();
+ 
+ int empno = call2.getInt(1);
+ 
+ show("Fetch second row of the ref cursor in PL/SQL: empno=" + empno);
+ 
+ // Dump the rest of the cursor
+ show("Fetch rest of the ref cursor rows in Java:");
+ while (rset.next ())
+ show(rset.getString ("EMPNO") + " "
+ + rset.getString ("ENAME"));
+ 
+ } // call2
+ } // rset
+ } // call1
+ }
+ 
+ // ==============================Utility Methods==============================
+
+ private void createFunctions() throws SQLException {
+ try (Statement stmt = conn.createStatement()) {
+ String sql = "CREATE OR REPLACE PACKAGE " + PACKAGE_NAME + " AS " +
+ " TYPE mycursortype IS REF CURSOR RETURN EMP%ROWTYPE; " +
+ " FUNCTION " + FUNCTION_NAME1 + " RETURN mycursortype; " +
+ " FUNCTION " + FUNCTION_NAME2 + " (mycursor mycursortype) RETURN NUMBER; " +
+ "END " + PACKAGE_NAME + ";";
+ 
+ stmt.execute (sql);
+ 
+ sql = "CREATE OR REPLACE PACKAGE BODY " + PACKAGE_NAME + " AS " +
+ " FUNCTION " + FUNCTION_NAME1 + " RETURN mycursortype IS " +
+ " rc mycursortype; " +
+ " BEGIN " +
+ " OPEN rc FOR SELECT * FROM emp ORDER BY empno;" +
+ " RETURN rc; " +
+ " END " + FUNCTION_NAME1 + "; " +
+ " " +
+ " FUNCTION " + FUNCTION_NAME2 + " (mycursor mycursortype) RETURN NUMBER IS " +
+ " rc NUMBER; " +
+ " myrecord EMP%ROWTYPE;" +
+ " BEGIN " +
+ " FETCH mycursor INTO myrecord;" +
+ " rc := myrecord.EMPNO;" +
+ " RETURN rc; " +
+ " END " + FUNCTION_NAME2 + "; " +
+ " " +
+ "END " + PACKAGE_NAME + ";";
+ 
+ stmt.execute (sql);
+ }
+ }
+
+ private void dropFunctions() throws SQLException {
+ try (Statement stmt = conn.createStatement()) {
+ stmt.execute ("DROP PACKAGE " + PACKAGE_NAME);
+ }
+ }
+ 
+ private Connection getConnection() throws SQLException {
+ // Create an OracleDataSource instance and set properties
+ OracleDataSource ods = new OracleDataSource();
+ ods.setUser(user);
+ ods.setPassword(password);
+ ods.setURL(url);
+
+ return ods.getConnection();
+ }
+
+ static void getRealUserPasswordUrl(String args[]) throws Exception {
+ // URL can be modified in file, or taken from command-line
+ url = getOptionValue(args, "-l", DEFAULT_URL);
+
+ // DB user can be modified in file, or taken from command-line
+ user = getOptionValue(args, "-u", DEFAULT_USER);
+
+ // DB user's password can be modified in file, or explicitly entered
+ readPassword(" Password for " + user + ": ");
+ }
+
+ // Get specified option value from command-line, or use default value
+ static String getOptionValue(String args[], String optionName,
+ String defaultVal) {
+ String argValue = "";
+
+ try {
+ int i = 0;
+ String arg = "";
+ boolean found = false;
+
+ while (i < args.length) {
+ arg = args[i++];
+ if (arg.equals(optionName)) {
+ if (i < args.length)
+ argValue = args[i++];
+ if (argValue.startsWith("-") || argValue.equals("")) {
+ argValue = defaultVal;
+ }
+ found = true;
+ }
+ }
+
+ if (!found) {
+ argValue = defaultVal;
+ }
+ } catch (Exception e) {
+ showError("getOptionValue", e);
+ }
+ return argValue;
+ }
+
+ static void readPassword(String prompt) throws Exception {
+ if (System.console() == null) {
+ BufferedReader r = new BufferedReader(new InputStreamReader(System.in));
+ shownln(prompt);
+ password = r.readLine();
+ } else {
+ char[] pchars = System.console().readPassword("\n[%s]", prompt);
+ if (pchars != null) {
+ password = new String(pchars);
+ java.util.Arrays.fill(pchars, ' ');
+ }
+ }
+ }
+
+ private static void show(String msg) {
+ System.out.println(msg);
+ }
+
+ // Show message line without new line
+ private static void shownln(String msg) {
+ System.out.print(msg);
+ }
+
+ static void showError(String msg, Throwable exc) {
+ System.out.println(msg + " hit error: " + exc.getMessage());
+ }
+}