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@beccam
Created June 27, 2014 19:54
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Getting Started with Apache Cassandra and Java
import com.datastax.driver.core.*;
public class GettingStarted {
public static void main(String[] args) {
Cluster cluster;
Session session;
// Connect to the cluster and keyspace "demo"
cluster = Cluster.builder().addContactPoint("127.0.0.1").build();
session = cluster.connect("demo");
// Insert one record into the users table
session.execute("INSERT INTO users (lastname, age, city, email, firstname) VALUES ('Jones', 35, 'Austin', 'bob@example.com', 'Bob')");
// Use select to get the user we just entered
ResultSet results = session.execute("SELECT * FROM users WHERE lastname='Jones'");
for (Row row : results) {
System.out.format("%s %d\n", row.getString("firstname"), row.getInt("age"));
}
// Update the same user with a new age
session.execute("update users set age = 36 where lastname = 'Jones'");
// Select and show the change
results = session.execute("select * from users where lastname='Jones'");
for (Row row : results) {
System.out.format("%s %d\n", row.getString("firstname"), row.getInt("age"));
}
// Delete the user from the users table
session.execute("DELETE FROM users WHERE lastname = 'Jones'");
// Show that the user is gone
results = session.execute("SELECT * FROM users");
for (Row row : results) {
System.out.format("%s %d %s %s %s\n", row.getString("lastname"), row.getInt("age"), row.getString("city"), row.getString("email"), row.getString("firstname"));
}
// Clean up the connection by closing it
cluster.close();
}
}
@iabhinay

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I am getting below error when i execute the file. I am using java 1.8:

[root@dbasandbox-test-1.avad tmp]# java -classpath cassandra-java-driver-2.0.2/:cassandra-java-driver-2.0.2/lib/:. GettingStarted
Exception in thread "main" java.lang.UnsupportedClassVersionError: GettingStarted : Unsupported major.minor version 52.0
at java.lang.ClassLoader.defineClass1(Native Method)
at java.lang.ClassLoader.defineClass(ClassLoader.java:800)
at java.security.SecureClassLoader.defineClass(SecureClassLoader.java:142)
at java.net.URLClassLoader.defineClass(URLClassLoader.java:449)
at java.net.URLClassLoader.access$100(URLClassLoader.java:71)
at java.net.URLClassLoader$1.run(URLClassLoader.java:361)
at java.net.URLClassLoader$1.run(URLClassLoader.java:355)
at java.security.AccessController.doPrivileged(Native Method)
at java.net.URLClassLoader.findClass(URLClassLoader.java:354)
at java.lang.ClassLoader.loadClass(ClassLoader.java:425)
at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:308)
at java.lang.ClassLoader.loadClass(ClassLoader.java:358)
at sun.launcher.LauncherHelper.checkAndLoadMain(LauncherHelper.java:482)

@LazyCoder88

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I am getting the below error when I am trying to execute this program.

Exception in thread "main" com.datastax.driver.core.exceptions.NoHostAvailableException: All host(s) tried for query failed (tried: /127.0.0.1:9042 (com.datastax.driver.core.ConnectionException: [/127.0.0.1:9042] Unexpected error during transport initialization (com.datastax.driver.core.TransportException: [/127.0.0.1:9042] Unexpected exception triggered (java.lang.IndexOutOfBoundsException: Not enough readable bytes - Need 4, maximum is 0))))
at com.datastax.driver.core.ControlConnection.reconnectInternal(ControlConnection.java:196)
at com.datastax.driver.core.ControlConnection.connect(ControlConnection.java:79)
at com.datastax.driver.core.Cluster$Manager.init(Cluster.java:1104)
at com.datastax.driver.core.Cluster.init(Cluster.java:121)
at com.datastax.driver.core.Cluster.connect(Cluster.java:198)
at com.datastax.driver.core.Cluster.connect(Cluster.java:226)
at com.practice.GettingStarted.main(GettingStarted.java:11)

Could you please help me out?

Thanks.

ghost commented Sep 13, 2016

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Has anyone solved the problem? I have the same problem.

@johnnydepup

johnnydepup commented Oct 4, 2016

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It is probably because the version of the driver being used is old. Use the recent version of the Java driver

@sreeladdu5

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Please check the version of java used for compiling the src code and jars added in classpath. It basically occurs when two versions of java are used in program.

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