src/share/classes/java/sql/DriverManager.java
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@@ -24,14 +24,14 @@
*/
package java.sql;
import java.util.Iterator;
-import java.sql.Driver;
import java.util.ServiceLoader;
import java.security.AccessController;
import java.security.PrivilegedAction;
+import java.util.concurrent.CopyOnWriteArrayList;
/**
* <P>The basic service for managing a set of JDBC drivers.<br>
* <B>NOTE:</B> The {@link <code>DataSource</code>} interface, new in the
@@ -77,10 +77,27 @@
* @see Connection
*/
public class DriverManager {
+ // List of registered JDBC drivers
+ private final static CopyOnWriteArrayList<Driver> registeredDrivers = new CopyOnWriteArrayList<Driver>();
+ private static volatile int loginTimeout = 0;
+ private static volatile java.io.PrintWriter logWriter = null;
+ private static volatile java.io.PrintStream logStream = null;
+ // Used in println() to synchronize logWriter
+ private static Object logSync = new Object();
+
+ /**
+ * Load the initial JDBC drivers by checking the System property
+ * jdbc.properties and then use the {@code ServiceLoader} mechanism
+ */
+ static {
+ loadInitialDrivers();
+ println("JDBC DriverManager initialized");
+ }
+
/**
* The <code>SQLPermission</code> constant that allows the
* setting of the logging stream.
* @since 1.3
*/
@@ -233,48 +250,37 @@
* that can connect to the given URL
* @exception SQLException if a database access error occurs
*/
public static Driver getDriver(String url)
throws SQLException {
- java.util.Vector drivers = null;
println("DriverManager.getDriver(\"" + url + "\")");
- if (!initialized) {
- initialize();
- }
-
- synchronized (DriverManager.class){
- // use the read copy of the drivers vector
- drivers = readDrivers;
- }
-
// Gets the classloader of the code that called this method, may
// be null.
ClassLoader callerCL = DriverManager.getCallerClassLoader();
- // Walk through the loaded drivers attempting to locate someone
+ // Walk through the loaded registeredDrivers attempting to locate someone
// who understands the given URL.
- for (int i = 0; i < drivers.size(); i++) {
- DriverInfo di = (DriverInfo)drivers.elementAt(i);
+ for (Driver aDriver : registeredDrivers) {
// If the caller does not have permission to load the driver then
// skip it.
- if ( getCallerClass(callerCL, di.driverClassName ) !=
- di.driverClass ) {
- println(" skipping: " + di);
- continue;
- }
+ if(isDriverAllowed(aDriver, callerCL)) {
try {
- println(" trying " + di);
- if (di.driver.acceptsURL(url)) {
+ if(aDriver.acceptsURL(url)) {
// Success!
- println("getDriver returning " + di);
- return (di.driver);
+ println("getDriver returning " + aDriver.getClass().getName());
+ return (aDriver);
}
- } catch (SQLException ex) {
+
+ } catch(SQLException sqe) {
// Drop through and try the next driver.
}
+ } else {
+ println(" skipping: " + aDriver.getClass().getName());
+ }
+
}
println("getDriver: no suitable driver");
throw new SQLException("No suitable driver", "08001");
}
@@ -290,27 +296,20 @@
* <code>DriverManager</code>
* @exception SQLException if a database access error occurs
*/
public static synchronized void registerDriver(java.sql.Driver driver)
throws SQLException {
- if (!initialized) {
- initialize();
- }
-
- DriverInfo di = new DriverInfo();
- di.driver = driver;
- di.driverClass = driver.getClass();
- di.driverClassName = di.driverClass.getName();
-
- // Not Required -- drivers.addElement(di);
-
- writeDrivers.addElement(di);
- println("registerDriver: " + di);
+ /* Register the driver if it has not already been added to our list */
+ if(driver != null) {
+ registeredDrivers.addIfAbsent(driver);
+ } else {
+ // This is for compatibility with the original DriverManager
+ throw new NullPointerException();
+ }
- /* update the read copy of drivers vector */
- readDrivers = (java.util.Vector) writeDrivers.clone();
+ println("registerDriver: " + driver);
}
/**
* Drops a driver from the <code>DriverManager</code>'s list.
@@ -319,41 +318,30 @@
* @param driver the JDBC Driver to drop
* @exception SQLException if a database access error occurs
*/
public static synchronized void deregisterDriver(Driver driver)
throws SQLException {
+ if (driver == null) {
+ return;
+ }
+
// Gets the classloader of the code that called this method,
// may be null.
ClassLoader callerCL = DriverManager.getCallerClassLoader();
println("DriverManager.deregisterDriver: " + driver);
- // Walk through the loaded drivers.
- int i;
- DriverInfo di = null;
- for (i = 0; i < writeDrivers.size(); i++) {
- di = (DriverInfo)writeDrivers.elementAt(i);
- if (di.driver == driver) {
- break;
- }
- }
- // If we can't find the driver just return.
- if (i >= writeDrivers.size()) {
- println(" couldn't find driver to unload");
- return;
- }
-
+ if(registeredDrivers.contains(driver)) {
+ if (isDriverAllowed(driver, callerCL)) {
+ registeredDrivers.remove(driver);
+ } else {
// If the caller does not have permission to load the driver then
- // throw a security exception.
- if (getCallerClass(callerCL, di.driverClassName ) != di.driverClass ) {
+ // throw a SecurityException.
throw new SecurityException();
}
-
- // Remove the driver. Other entries in drivers get shuffled down.
- writeDrivers.removeElementAt(i);
-
- /* update the read copy of drivers vector */
- readDrivers = (java.util.Vector) writeDrivers.clone();
+ } else {
+ println(" couldn't find driver to unload");
+ }
}
/**
* Retrieves an Enumeration with all of the currently loaded JDBC drivers
* to which the current caller has access.
@@ -362,38 +350,26 @@
* <CODE>d.getClass().getName()</CODE>
*
* @return the list of JDBC Drivers loaded by the caller's class loader
*/
public static java.util.Enumeration<Driver> getDrivers() {
- java.util.Vector<Driver> result = new java.util.Vector<>();
- java.util.Vector drivers = null;
-
- if (!initialized) {
- initialize();
- }
-
- synchronized (DriverManager.class){
- // use the readcopy of drivers
- drivers = readDrivers;
- }
+ java.util.Vector<Driver> result = new java.util.Vector<Driver>();
// Gets the classloader of the code that called this method, may
// be null.
ClassLoader callerCL = DriverManager.getCallerClassLoader();
- // Walk through the loaded drivers.
- for (int i = 0; i < drivers.size(); i++) {
- DriverInfo di = (DriverInfo)drivers.elementAt(i);
+ // Walk through the loaded registeredDrivers.
+ for(Driver aDriver : registeredDrivers) {
// If the caller does not have permission to load the driver then
// skip it.
- if ( getCallerClass(callerCL, di.driverClassName ) != di.driverClass ) {
- println(" skipping: " + di);
- continue;
+ if(isDriverAllowed(aDriver, callerCL)) {
+ result.addElement(aDriver);
+ } else {
+ println(" skipping: " + aDriver.getClass().getName());
}
- result.addElement(di.driver);
}
-
return (result.elements());
}
/**
@@ -479,25 +455,26 @@
}
}
//------------------------------------------------------------------------
- // Returns the class object that would be created if the code calling the
- // driver manager had loaded the driver class, or null if the class
- // is inaccessible.
- private static Class getCallerClass(ClassLoader callerClassLoader,
- String driverClassName) {
- Class callerC = null;
-
+ // Indicates whether the class object that would be created if the code calling
+ // DriverManager is accessible.
+ private static boolean isDriverAllowed(Driver driver, ClassLoader classLoader) {
+ boolean result = false;
+ if(driver != null) {
+ Class<?> aClass = null;
try {
- callerC = Class.forName(driverClassName, true, callerClassLoader);
+ aClass = Class.forName(driver.getClass().getName(), true, classLoader);
+ } catch (Exception ex) {
+ result = false;
}
- catch (Exception ex) {
- callerC = null; // being very careful
+
+ result = ( aClass == driver.getClass() ) ? true : false;
}
- return callerC;
+ return result;
}
private static void loadInitialDrivers() {
String drivers;
try {
@@ -542,29 +519,20 @@
return null;
}
});
println("DriverManager.initialize: jdbc.drivers = " + drivers);
- if (drivers == null) {
+
+ if (drivers == null || drivers.equals("")) {
return;
}
- while (drivers.length() != 0) {
- int x = drivers.indexOf(':');
- String driver;
- if (x < 0) {
- driver = drivers;
- drivers = "";
- } else {
- driver = drivers.substring(0, x);
- drivers = drivers.substring(x+1);
- }
- if (driver.length() == 0) {
- continue;
- }
+ String[] driversList = drivers.split(":");
+ println("number of Drivers:" + driversList.length);
+ for (String aDriver : driversList) {
try {
- println("DriverManager.Initialize: loading " + driver);
- Class.forName(driver, true,
+ println("DriverManager.Initialize: loading " + aDriver);
+ Class.forName(aDriver, true,
ClassLoader.getSystemClassLoader());
} catch (Exception ex) {
println("DriverManager.Initialize: load failed: " + ex);
}
}
@@ -572,11 +540,10 @@
// Worker method called by the public getConnection() methods.
private static Connection getConnection(
String url, java.util.Properties info, ClassLoader callerCL) throws SQLException {
- java.util.Vector drivers = null;
/*
* When callerCl is null, we should check the application's
* (which is invoking this class indirectly)
* classloader, so that the JDBC driver class outside rt.jar
* can be loaded from here.
@@ -592,44 +559,36 @@
throw new SQLException("The url cannot be null", "08001");
}
println("DriverManager.getConnection(\"" + url + "\")");
- if (!initialized) {
- initialize();
- }
-
- synchronized (DriverManager.class){
- // use the readcopy of drivers
- drivers = readDrivers;
- }
-
- // Walk through the loaded drivers attempting to make a connection.
+ // Walk through the loaded registeredDrivers attempting to make a connection.
// Remember the first exception that gets raised so we can reraise it.
SQLException reason = null;
- for (int i = 0; i < drivers.size(); i++) {
- DriverInfo di = (DriverInfo)drivers.elementAt(i);
+ for(Driver aDriver : registeredDrivers) {
// If the caller does not have permission to load the driver then
// skip it.
- if ( getCallerClass(callerCL, di.driverClassName ) != di.driverClass ) {
- println(" skipping: " + di);
- continue;
- }
+ if(isDriverAllowed(aDriver, callerCL)) {
try {
- println(" trying " + di);
- Connection result = di.driver.connect(url, info);
- if (result != null) {
+ println(" trying " + aDriver.getClass().getName());
+ Connection con = aDriver.connect(url, info);
+ if (con != null) {
// Success!
- println("getConnection returning " + di);
- return (result);
+ println("getConnection returning " + aDriver.getClass().getName());
+ return (con);
}
} catch (SQLException ex) {
if (reason == null) {
reason = ex;
}
}
+
+ } else {
+ println(" skipping: " + aDriver.getClass().getName());
+ }
+
}
// if we got here nobody could connect.
if (reason != null) {
println("getConnection failed: " + reason);
@@ -638,47 +597,12 @@
println("getConnection: no suitable driver found for "+ url);
throw new SQLException("No suitable driver found for "+ url, "08001");
}
-
- // Class initialization.
- static void initialize() {
- if (initialized) {
- return;
- }
- initialized = true;
- loadInitialDrivers();
- println("JDBC DriverManager initialized");
- }
-
/* Prevent the DriverManager class from being instantiated. */
private DriverManager(){}
- /* write copy of the drivers vector */
- private static java.util.Vector writeDrivers = new java.util.Vector();
-
- /* write copy of the drivers vector */
- private static java.util.Vector readDrivers = new java.util.Vector();
-
- private static int loginTimeout = 0;
- private static java.io.PrintWriter logWriter = null;
- private static java.io.PrintStream logStream = null;
- private static boolean initialized = false;
-
- private static Object logSync = new Object();
-
/* Returns the caller's class loader, or null if none */
private static native ClassLoader getCallerClassLoader();
}
-
-// DriverInfo is a package-private support class.
-class DriverInfo {
- Driver driver;
- Class driverClass;
- String driverClassName;
-
- public String toString() {
- return ("driver[className=" + driverClassName + "," + driver + "]");
- }
-}