alexradzin’s gists

alexradzin / Insert.java

Created November 21, 2021 07:10

Insert rows to a database using regular and prepared statement utilizing one-by-one and batch mode

+package org.jdbc.test;
+import java.sql.Connection;
+import java.sql.PreparedStatement;
+import java.sql.SQLException;
+import java.sql.Statement;
+import static java.lang.String.format;
+public class Insert {

alexradzin / Initialization.java

Created October 31, 2021 08:28

Variables initialization

	import java.util.AbstractMap;
	import java.util.Arrays;
	import java.util.Collections;
	import java.util.HashMap;
	import java.util.HashSet;
	import java.util.LinkedHashMap;
	import java.util.LinkedHashSet;
	import java.util.List;
	import java.util.Map;
	import java.util.Set;

alexradzin / build_patch.sh

Last active September 12, 2019 07:44

Patch for the Hive JDBC driver under spark

	#!/bin/sh

	# This file shoule be copied to src/java/ and executed from this directory
	JARS=../../jars
	CP=$JARS/hive-service-1.2.1.jar:$JARS/hive-jdbc-1.2.1.jar:$JARS/commons-logging-1.1.3.jar:$JARS/libthrift-0.9.3.jar
	javac -cp $CP org/apache/hive/jdbc/HiveStatement.java
	javac -cp $CP org/apache/hive/jdbc/HivePreparedStatement.java
	javac -cp $CP org/apache/hive/jdbc/HiveResultSetMetaData.java

	cp $JARS/hive-jdbc-1.2.1.jar $JARS/hive-jdbc-1.2.1_patch.jar

alexradzin / Book.java

Created February 12, 2019 00:21

Improved Visitor

	package visitor;

	public class Book implements Visitable {
	private final String title;
	private final int pageCount;

	public Book(String title, int pageCount) {
	this.title = title;
	this.pageCount = pageCount;
	}

alexradzin / SyntaxHighlighter by reference

Last active February 1, 2019 20:35

SyntaxHighlighter

	<link href='http://alexgorbatchev.com/pub/sh/current/styles/shCore.css' rel='stylesheet' type='text/css'/>
	<link href='http://alexgorbatchev.com/pub/sh/current/styles/shThemeDefault.css' rel='stylesheet' type='text/css'/>
	<script src='http://alexgorbatchev.com/pub/sh/current/scripts/shCore.js' type='text/javascript'></script>
	<script src='http://alexgorbatchev.com/pub/sh/current/scripts/shBrushCpp.js' type='text/javascript'></script>
	<script src='http://alexgorbatchev.com/pub/sh/current/scripts/shBrushCSharp.js' type='text/javascript'></script>
	<script src='http://alexgorbatchev.com/pub/sh/current/scripts/shBrushCss.js' type='text/javascript'></script>
	<script src='http://alexgorbatchev.com/pub/sh/current/scripts/shBrushJava.js' type='text/javascript'></script>
	<script src='http://alexgorbatchev.com/pub/sh/current/scripts/shBrushJScript.js' type='text/javascript'></script>
	<script src='http://alexgorbatchev.com/pub/sh/current/scripts/shBrushPhp.js' type='text/javascript'></script>
	<script src='http:/

alexradzin / EnumSwitch.java

Last active January 30, 2019 20:42

	enum Action {ONE, TWO, THREE}
	// ..........
	Action a = ...
	switch (a) {
	case ONE: one(); break;
	case TWO: two(); break;
	case THREE: three(); break;
	default: throw new UnsupportedOperationException(String.format("Operation %s is not supported", a));
	}

alexradzin / Color.java

Last active March 12, 2019 06:30

Simple utility that helps to create mirror enums safe for modification of the source enum.

	public enum Color {
	RED, GREEN, BLUE,;

	static {
	Mirror.of(RGB.class);
	}
	}

alexradzin / String.format.vm

Created December 3, 2018 18:27

Velocity template for IntelliJ Idea Java IDE. This template generates toString() implementations using String.format()

	public java.lang.String toString() {
	#if ( $members.size() > 0 )
	#set ( $i = 0 )
	return String.format("$classname{#foreach( $member in $members )$member.name=%s#if ( $i < $members.size() - 1 ), #end#set ( $i = $i + 1 )#end}"#foreach( $member in $members ),#if ( $member.objectArray )$member.accessor == null ? null : java.util.Arrays.asList($member.accessor)#else$member.accessor#end#end);
	#else
	return "$classname{}";
	#end
	}

alexradzin / TryPerf.java

Created March 17, 2016 13:48

try/catch/finally performance

	public class TryPerf {
	private static int foo(int a) {
	return a * 2;
	}


	private static int tryFinally(int a) {
	try {
	return a * 2;
	} finally {

alexradzin / FormatterExercise.java

Created February 24, 2016 14:58

LocalesFormat Iterates over all locale available on current system and prints locale that use special characters to present digits. It also counts how many locales use dot and comma as a decimal delimiter. FormatterExercise compares performance of String.format() vs direct usage of Formatter class.

	import java.util.Formatter;

	public class FormatterExercise {
	private static int n = 1_000_000;

	public static void main(String[] args) throws InterruptedException {
	long before = System.nanoTime();
	str();
	long after = System.nanoTime();
	System.out.println((after - before)/1_000_000);

Alexander Radzin alexradzin