/**
* Copyright 2007-2011 Zuse Institute Berlin
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package de.zib.scalaris.examples;
import com.ericsson.otp.erlang.OtpErlangList;
import com.ericsson.otp.erlang.OtpErlangString;
import de.zib.scalaris.AbortException;
import de.zib.scalaris.ConnectionException;
import de.zib.scalaris.NotFoundException;
import de.zib.scalaris.TimeoutException;
import de.zib.scalaris.Transaction;
import de.zib.scalaris.UnknownException;
/**
* Provides an example for using the <code>read</code> method of the
* {@link Transaction} class.
*
* @author Nico Kruber, kruber@zib.de
* @version 2.0
* @since 2.0
*/
public class TransactionReadExample {
/**
* Reads all keys given on the command line (given as "key1 key2 ...") with
* the {@link Transaction#read(String)} and
* {@link Transaction#read(OtpErlangString)} methods in a single
* transaction.<br />
* If no keys are given, the default keys <code>"key1"</code>, <code>"key2"</code>,
* <code>"key3"</code> are used.
*
* @param args
* command line arguments (optional keys to look up)
*/
public static void main(final String[] args) {
String[] keys;
String value;
if (args.length == 0) {
keys = new String[] { "key1", "key2", "key3" };
} else {
keys = args;
}
final OtpErlangString[] otpKeys_temp = new OtpErlangString[keys.length];
for (int i = 0; i < keys.length; ++i) {
otpKeys_temp[i] = new OtpErlangString(keys[i]);
}
final OtpErlangList otpKeys = (new OtpErlangList(otpKeys_temp));
OtpErlangString otpValue;
System.out.println("Reading values with the class `Transaction`:");
System.out.print(" Initialising Transaction object... ");
try {
final Transaction transaction = new Transaction();
System.out.println("done");
System.out.print(" Starting transaction... ");
System.out.println("done");
System.out
.println(" `OtpErlangObject readObject(OtpErlangString)`...");
for (int i = 0; i < otpKeys.arity(); ++i) {
final OtpErlangString otpKey = (OtpErlangString) otpKeys.elementAt(i);
try {
otpValue = (OtpErlangString) transaction.read(otpKey).value();
System.out.println(" read(" + otpKey.stringValue()
+ ") == " + otpValue.stringValue());
} catch (final ConnectionException e) {
System.out.println(" read(" + otpKey.stringValue()
+ ") failed: " + e.getMessage());
} catch (final TimeoutException e) {
System.out.println(" read(" + otpKey.stringValue()
+ ") failed with timeout: " + e.getMessage());
} catch (final UnknownException e) {
System.out.println(" read(" + otpKey.stringValue()
+ ") failed with unknown: " + e.getMessage());
} catch (final NotFoundException e) {
System.out.println(" read(" + otpKey.stringValue()
+ ") failed with not found: " + e.getMessage());
} catch (final ClassCastException e) {
System.out.println(" read(" + otpKey.stringValue()
+ ") failed with unknown return type: " + e.getMessage());
}
}
System.out.println(" `String read(String)`...");
for (int i = 0; i < keys.length; ++i) {
final String key = keys[i];
try {
value = transaction.read(key).stringValue();
System.out.println(" read(" + key + ") == " + value);
} catch (final ConnectionException e) {
System.out.println(" read(" + key + ") failed: "
+ e.getMessage());
} catch (final TimeoutException e) {
System.out.println(" read(" + key
+ ") failed with timeout: " + e.getMessage());
} catch (final UnknownException e) {
System.out.println(" read(" + key
+ ") failed with unknown: " + e.getMessage());
} catch (final NotFoundException e) {
System.out.println(" read(" + key
+ ") failed with not found: " + e.getMessage());
}
}
System.out.print(" Committing transaction... ");
transaction.commit();
System.out.println("done");
} catch (final ConnectionException e) {
System.out.println("failed: " + e.getMessage());
return;
} catch (final TimeoutException e) {
System.out.println("failed: " + e.getMessage());
return;
} catch (final AbortException e) {
System.out.println("failed: " + e.getMessage());
return;
} catch (final UnknownException e) {
System.out.println("failed: " + e.getMessage());
return;
}
}
}