© 2026 Machinery For Change LLC
This software is made available for use, modification, and redistribution, under the terms of the Lesser GNU Public License, v.2.1 (LGPL) or the Eclipse Public License, v.1.0 (EPL), at your option. You should have received copies of both licenses with this distribution. You may also opt to license this software under a more recent version of LGPL than v.2.1.
You'll find this version on the Maven Central repository — com.mchange:c3p0:0.13.0
For support of asynchrony via Java 21 "loom" virtual threads, use instead — com.mchange:c3p0-loom:0.13.0
To its author's profound shame, c3p0, along with its supporting libraries, was used for about a decade as a "deserialization gadget". If an attacker is able to replace and maliciously recraft a javax.naming.Reference or Java-serialized object that an application will decode, c3p0's libraries could be misused to expand that access into execution of arbitrary malicious code.
c3p0-0.12.0, along with its dependency mchange-commons-java-0.4.0, includes mitigations that lock down the functionality misused as gadget chains.
Although it remains possible to resurrect and make use of the dangerous functionality, it requires new, affirmative configuration, and very few contemporary applications should do so.
Most installations will not, but if you experience breaking changes in c3p0-0.12.0, you may need to customize security configuration for your deployment. Please see Configuring Security below for information on how, and for more background on the security issues.
c3p0-0.13.0, with mchange-commons-java-0.5.0, eliminates all use of Java serialization in resolving References, definitively ending any possibility of misuse of c3p0-related JNDI utilities to construct deserialization gadgets.
Many thanks to David Pollak of Spice Labs for a very detailed report about this issue.
See also Warning: c3p0 trusts its CLASSPATH and configuration.
c3p0 was designed to be butt-simple to use.
Just bring Maven dependency com.mchange:c3p0:0.13.0 into your application's effective CLASSPATH (which should bring along its one transitive dependency, mchange-commons-java). Then make a DataSource like this:
[Optional] If you want to turn on PreparedStatement pooling, you must also set maxStatements and/or maxStatementsPerConnection (both default to 0):
Do whatever you want with your DataSource, which will be backed by a Connection pool set up with default parameters. You can bind the DataSource to a JNDI name service, or use it directly, as you prefer.
When you are done, you can clean up the DataSource you've created like this:
That's it! The rest is detail.
c3p0 is an easy-to-use library for making traditional JDBC drivers "enterprise-ready" by augmenting them with functionality defined by the jdbc3 spec and the optional extensions to jdbc2. c3p0 now also fully supports the jdbc4.
In particular, c3p0 provides several useful services:
The library tries hard to get the details right:
c3p0 hopes to provide DataSource implementations more than suitable for use by high-volume "J2EE enterprise applications". Please provide feedback, bug-fixes, etc!
c3p0-0.13.0 requires a level 1.7.x or above Java Runtime Environment.
There is no installation beyond accessing managed Maven dependency com.mchange:c3p0:0.13.0.
If you wish to make use of Java 21 ("loom") virtual threading, use com.mchange:c3p0-loom:0.13.0 instead.
If you want to install c3p0 by hand, just place the files c3p0-0.13.0.jar and mchange-commons-java-0.5.0.jar somewhere in your CLASSPATH (or any other place where your application's classloader will find it). For Java 21 "loom" support, also include the jar c3p0-loom-0.13.0.jar.
Proceed with caution and respect.
If you are a creator looking to enter this space:
Bottom Line: The market is saturated with surface-level content, but starved for depth, accuracy, and modernity. The creator who bridges ancient tradition with contemporary, messy, real life will win.
Frozy Material Design Icon Pack by developer Fraom Design is a premium customization tool for Android that offers a vibrant, redesigned take on Google's Material Design language. Version 33 (v33) continues the tradition of providing high-quality, colorful icons and extensive launcher support. Google Play Key Features of Frozy Icon Pack Icon Library : Includes over 2,200 icons
in full HD quality, featuring bright and vivid color palettes. System Icons
: Provides dedicated stock system icons for major manufacturers like Samsung, HTC, Asus, Huawei, Sony, and Xiaomi Extra Content Cloud Wallpapers
: A collection of wallpapers with Muzei support to match the icon aesthetic. Dynamic Calendars
: Support for popular calendar apps to show the correct date on the icon. Utility Tools
: Includes a search tool for finding specific icons and a request tool for missing icons. Google Play Compatibility and Requirements
Frozy is not a standalone application and requires a custom launcher to function. It is compatible with: Popular Launchers : Nova, Apex, Action, Smart, Adw, and Lawnchair. Modded Options
: Works with modded versions of Pixel Launcher (stock Pixel, Google Now, and MIUI launchers typically support icon packs natively). Google Play Downloading Frozy v33 The most secure way to obtain the Frozy Material Design Icon Pack is through the Google Play Store , where it is currently listed as a paid app. Google Play Safety Warning
: While "v33 apk" links may appear on third-party sites, downloading APKs from unofficial sources carries significant security risks, including malware. Using the official store ensures you receive automatic weekly updates and verified safety. Google Play or see how this pack compares to other Material You Frozy / Material Design Icon P - Apps on Google Play
Feature: Precision-Crafted Adaptive Iconography with Dynamic Calendar Support
The Frozy Material Design Icon Pack v33 distinguishes itself through a rigorous adherence to Google’s Material Design 2.0 guidelines, offering users a cohesive visual language characterized by soft, frosted-glass textures and a soothing pastel color palette.
A key informative feature of this release is its comprehensive implementation of Dynamic Calendar Support. Unlike standard icon packs that merely mask icons, Frozy v33 integrates deeply with the Android system to automatically update the icons of calendar applications (such as Google Calendar) to display the current date. This ensures that the aesthetic consistency remains unbroken even by functional, time-sensitive apps.
Additionally, the v33 update introduces an expanded library of over 50 new icons, specifically targeting newly released apps and persistent user requests. The pack utilizes high-resolution iconography (XXXHDPI), ensuring that icons retain their crisp, detailed edges even on high-density displays (2K/4K screens) without appearing pixelated. The "Frozy" effect is achieved through custom-designed vectors that simulate a matte finish, providing a uniform look that blends seamlessly with both dark and light themes.
Introduction
Frozy Material Design Icon Pack is a popular icon pack that offers a wide range of material design icons for Android users. The pack is designed to give your device a fresh and modern look. In this guide, we will walk you through the process of downloading and installing Frozy Material Design Icon Pack v33 APK.
Features of Frozy Material Design Icon Pack
Downloading and Installing Frozy Material Design Icon Pack v33 APK
How to Apply Frozy Material Design Icon Pack on Different Launchers
Tips and Tricks
Conclusion
Frozy Material Design Icon Pack v33 APK is a great way to give your device a fresh and modern look. With its wide range of material design icons and regular updates, it's a popular choice among Android users. By following this guide, you can easily download and install the icon pack on your device.
The Frozy / Material Design Icon Pack is an Android customization app created by Fraom Design that provides over 2,200 full HD icons with a modern, vibrant material aesthetic. Official Download Link
The safest and most recommended way to download and install this icon pack is through the Google Play Store. Key Features & Requirements
Compatibility: This pack requires a custom launcher to work. Tested and compatible launchers include Nova, Apex, Action, Lawnchair, and Evie.
Stock Launchers: Standard launchers like Pixel Launcher, Google Now Launcher, and MIUI Launcher do not natively support this icon pack unless you use a modded version or shortcut tools. frozy material design icon pack v33 apk link
Updates: The pack includes dynamic calendar support, cloud-based wallpapers, and a built-in icon request tool for missing apps.
Installation: To apply, open your launcher settings, navigate to the "Appearance" or "Icon Pack" section, and select Frozy. Security Warning
While third-party APK mirror sites may host "v33" versions, downloading from unofficial sources poses security risks like malware or outdated builds. For a secure experience and future update notifications, always prioritize the official Google Play Store listing. Frozy / Material Design Icon P - Apps on Google Play
Yes, young Indians wear Zara and H&M. But the most "fashionable" thing you can wear to a wedding or a temple is still a six-yard saree or a crisp kurta.
There is a resurgence happening right now. Gen Z is rejecting fast fashion in favor of handloom cotton and block prints. Why wear a synthetic dress when you can wear a saree that breathes in 40-degree heat? The Indian wardrobe is sustainable, stunning, and deeply connected to the weaver’s art.
Why is this icon pack so popular among Android enthusiasts? Here are the standout features you can expect in the latest v33 update:
If you have decided to source the APK manually, follow these steps carefully. We cannot host the file directly, but we will tell you exactly how to find a safe version.
Summary
Frozy Material Design Icon Pack v33 is an icon theme aimed at Android users who prefer clean, minimal Material-style icons with subtle flat shadows and a consistent color palette. Version 33 updates icon coverage, refines glyphs, and adds new wallpapers.
Design & Visuals
Icon Coverage & Theming
Performance & Compatibility
What’s New in v33
Pros
Cons
Who it’s for
Verdict Frozy Material Design Icon Pack v33 is a well-crafted, minimalist icon pack that refreshes many core icons and adds tasteful wallpapers; it’s a solid choice for launcher users seeking a consistent Material aesthetic, provided you’re willing to accept occasional generic fallbacks and ensure you install the APK from a trusted source.
Related search suggestions (optional follow-ups) (Invoking related search-term helper...)
🎨 Fresh Look for Your Android: Frozy Icon Pack v33 If you are looking to give your Android home screen a vibrant, modern makeover, Frozy - Material Design Icon Pack by Fraom Fantasy is a top-tier choice. Known for its brilliant, vivid colors and super-crisp material design effects, this pack breathes new life into your device with a unique "frosted" aesthetic. What’s Inside the Latest Updates?
While version numbers may vary by platform, the latest builds typically include:
2,200+ High-Definition Icons: Redesigned from the ground up for maximum clarity.
Broad Device Support: Includes stock system icons for major brands like Samsung, OnePlus, Sony, Xiaomi, and more.
Cloud Wallpapers: A collection of matching backgrounds with Muzei support to complete your look.
Dynamic Features: Supports dynamic calendar icons and includes an easy-to-use search tool. Compatibility & Installation
To use Frozy, you’ll need a custom launcher. It is fully compatible with:
Popular Launchers: Nova, Apex, Action Launcher, Smart Launcher, and Lawnchair.
Pixel/One UI: Works on Pixel devices (using Shortcut Maker) and Samsung One UI (via Theme Park). 📥 Official Download Link
To ensure you have the most secure and up-to-date version, always download directly from the official store: Get it on the Google Play Store. Proceed with caution and respect
Note: Avoid third-party APK mirrors to protect your device from security risks and to ensure you receive future weekly updates automatically.
Frozy Material Design Icon Pack v33 APK Link: A Comprehensive Guide
In the world of Android customization, icon packs play a significant role in personalizing the look and feel of a device. One of the most popular and highly sought-after icon packs is the Frozy Material Design Icon Pack. With its sleek and modern design, it's no wonder that users are eager to get their hands on the latest version, specifically Frozy Material Design Icon Pack v33.
In this article, we'll provide an in-depth look at the Frozy Material Design Icon Pack, its features, and most importantly, we'll share the APK link for version v33.
What is Frozy Material Design Icon Pack?
Frozy Material Design Icon Pack is a popular icon pack designed for Android devices. It offers a wide range of icons that follow the Material Design guidelines, providing a cohesive and visually appealing look. The pack is designed to be compatible with various launchers, including popular ones like Nova Launcher, Apex Launcher, and more.
Key Features of Frozy Material Design Icon Pack
Before we dive into the details of version v33, let's take a look at some of the key features that make Frozy Material Design Icon Pack a favorite among Android enthusiasts:
What's New in Frozy Material Design Icon Pack v33?
The latest version, v33, brings several exciting updates and additions to the table. Some of the notable changes include:
Frozy Material Design Icon Pack v33 APK Link
For those eager to try out the latest version, we've got you covered. Here's the direct APK link for Frozy Material Design Icon Pack v33:
[Insert APK link]
How to Install Frozy Material Design Icon Pack v33 APK
Installing the icon pack is a straightforward process:
Tips and Tricks for Using Frozy Material Design Icon Pack
To get the most out of the icon pack, here are a few tips:
Conclusion
Frozy Material Design Icon Pack v33 is a fantastic option for Android users looking to give their device a fresh and modern look. With its extensive icon collection, Material Design aesthetic, and customizable features, it's no wonder that this icon pack has gained a significant following.
By following this guide, you should be able to easily download and install Frozy Material Design Icon Pack v33 APK. If you have any questions or need further assistance, feel free to leave a comment below.
Disclaimer
The APK link provided is for educational purposes only. We do not host or distribute copyrighted materials. Users are advised to ensure they have the necessary permissions and rights to use the software.
About the Author
[Your Name] is a tech enthusiast with a passion for Android customization. With years of experience in writing about Android apps and icon packs, [Your Name] aims to provide informative and engaging content for the Android community.
Frozy - Material Design Icon Pack is an Android personalization app developed by Fraom Design
, known for its vibrant and vivid material design-inspired icons. Google Play Official Download & App Information
The safest and most reliable way to download Frozy is through the Google Play Store Developer: Fraom Design Typically around Icon Count: Features over 2,200 HD icons Key Features: Bottom Line: The market is saturated with surface-level
Includes alternative colorful icons, cloud-based wallpapers (Muzei support), dynamic calendar support, and an icon request tool. Compatibility: Works with most popular custom launchers such as Nova Launcher , Apex, Action, and Lawnchair Launcher Google Play Important Version Note
While users often search for specific version APKs like "v33," official records indicate that major updates for Frozy peaked around Version 4.0
in late 2018. If you are looking for a more modern "frosted" aesthetic, the newer Frosty Icons Pack SK wallpapers
is currently maintained with updates as recent as late 2025. Google Play How to Install and Apply Install the icon pack from the Google Play Store Open Launcher Settings: Long-press your home screen and select Look & Feel Apply Icons: Icon Style Icon Theme menu and select from the list of installed packs. Manual Application:
If your launcher is not automatically detected, most launchers allow you to manually select individual icons by long-pressing a specific app and choosing "Edit". Google Play alternative material design icon packs that are currently receiving monthly updates? AI responses may include mistakes. Learn more Frozy / Material Design Icon P - Apps on Google Play
Here’s a creative and engaging text on Indian culture and lifestyle — designed to feel vivid, insightful, and shareable.
Title: Where Every Day is a Festival: Unpacking the Beautiful Chaos of Indian Culture & Lifestyle
Step into India, and you don’t just visit a country—you enter a living, breathing mosaic of contradictions that somehow make perfect sense.
The Rhythm of the Clock
Forget rigid schedules. In India, life runs on “Indian Stretchable Time”—a fluid rhythm where a 5-minute chai break stretches into an hour of philosophy, gossip, and solving the world’s problems over a steaming clay cup. Here, punctuality takes a backseat to presence.
Home as a Temple, Street as a Stage
Morning begins not with coffee, but with the smell of incense and jasmine. A grandmother draws a kolam (rice flour rangoli) at the doorstep—an art form that feeds ants and welcomes goddesses. Inside, the pressure cooker whistles like a train, while 17 different spices wait in steel dabba boxes. Every home has a prayer corner, a mango pickle jar older than you, and an unspoken rule: Never refuse food. Ever.
The Wardrobe That Speaks Volumes
A silk saree with gold borders isn’t just clothing—it’s a grandmother’s legacy. A crisp white dhoti is politics. A pair of faded jeans with a bindi? That’s modern India. From the handloom weaves of Varanasi to the mirrored skirts of Gujarat, every drape tells a story of geography, caste, climate, and celebration. And yes, even the simplest cotton kurta has pockets deep enough to hold a phone, keys, and a small mango.
Chaos as Choreography
The street is where India reveals its soul. Cows nap in the middle of a highway; autos weave like water molecules; a chai wallah pours hot tea from a meter-high arc without spilling a drop. Over the roar of traffic, you’ll hear a bhajan from a temple, the azan from a mosque, and a Bollywood item number from a phone shop—all in perfect dissonance. And somehow, nobody flinches.
The Festival Inside You
In the West, you go to a festival. In India, festivals possess the air.
And that’s just the national list. Every village has its own deity, its own harvest dance, its own reason to celebrate a full moon.
Eating with Your Hands & Heart
Forget forks. The real test of belonging is eating rice and sambar with your fingers—feeling the heat, mixing textures, and knowing that the thumb, index, and middle finger are not just tools but conduits of gratitude. A proper South Indian meal is served on a banana leaf, each vegetable occupying a precise spot like planets in a solar system. And if you leave food on your plate, you might as well insult someone’s mother.
Modern Meets Ancient: The Urban Shuffle
In Mumbai, a fintech CEO wears sneakers with a bandhgala jacket. In Bengaluru, techies discuss startup valuations while sipping filter coffee from steel tumblers. Arranged marriages now begin with a DM and a horoscope PDF. Yoga isn’t a wellness trend—it’s a grandfather’s 5 AM ritual, now livestreamed. India doesn’t abandon tradition; it just gives it an Instagram filter.
The Unspoken Glue: "Adjust Maadi"
The most Indian word isn’t namaste—it’s adjust. It means: make space, be flexible, share the train seat, eat the extra chapati, let the neighbor’s music play loud tonight. This ability to absorb contradiction—poverty next to luxury, ancient next to AI—is India’s real superpower.
Final Frame
To live the Indian lifestyle is to accept that the milk will boil over exactly when you’re on an important call, that the power will cut during the final scene of a movie, and that your aunt will ask why you’re still single. And yet, you’ll find yourself smiling. Because here, life isn’t a problem to solve—it’s a spice to savor. Thoda teekha, thoda meetha. (A little spicy, a little sweet.)
Would you like a shorter version for Instagram captions or a more research-based tone for an article?
Frozy / Material Design Icon Pack , developed by Fraom Design
, is a premium personalization app for Android that offers over 2,200 full HD icons with vivid colors and a redesigned material style. Google Play While you are looking for , the official versioning on the Google Play Store
typically follows a different numbering format (the last recorded update was in 2018). Google Play Official Download & Safety
To ensure you receive the most secure and up-to-date version, it is highly recommended to use the official store link. Using unofficial "APK link" sites can expose your device to security risks. Official Store : You can find the app on the Google Play Store for approximately Alternative Source
: Some versions, such as v4.0, have been listed on community repositories like Droid Informer Google Play Key Features of Frozy Extensive Library
: Includes over 2,200 icons and stock system icons for major manufacturers like Samsung, HTC, and Sony. Customization
: Offers alternative colorful icons, cloud-based wallpapers with Muzei support, and dynamic calendar support. Launcher Compatibility
: Requires a custom launcher to function. It is compatible with: Nova Launcher Apex Launcher Action Launcher Lawnchair Launcher Evie Launcher Google Play Free Alternatives
If you are looking for free material-themed icon packs, consider these highly-rated options: MaterialOS : An open-source pack with over 450 icons. Delta Icon Pack : A popular minimalistic pastel-colored pack. Arcticons Material You : A line-based pack that adapts to your system colors. Frozy / Material Design Icon P - Apps on Google Play
Use these well-known, vetted APK repositories:
These utilities are no longer supported. Please use Connection.unwrap(...) to access Oracle-specific APIs.
The Oracle thin JDBC driver provides a non-standard API for creating temporary BLOBs and CLOBs that
requires users to call methods on the raw, Oracle-specific Connection implementation. Advanced users
might use the raw connection operations described above to access this
functionality, but a convenience class is available in a separate jar file (c3p0-oracle-thin-extras-0.13.0.jar)
for easier access to this functionality. Please see the
API docs for com.mchange.v2.c3p0.dbms.OracleUtils
for details.
As of c3p0 0.10.0, c3p0's config property connectionTesterClassName defaults to null. When this property is null, c3p0 just uses the Java 6+ Connection.isValid(int timeout) method to test Connections.
But c3p0 is an old library, first published uner Java 1.3. Back in the day, we didn't have no stinking standard Connection.isValid(int timeout) method, and had to roll our own Connection tests. This Appendix documents that old but still supported style of Connection test management. To make this section relevant again, just 1) set connectionTesterClassName to its old default of com.mchange.v2.c3p0.DefaultConnectionTester; 2) set connectionTesterClassName to the name of a custom ConnectionTester implementation with a public no-arg constructor; 3) set a non-null preferredTestQuery; or 4) set a non-null automaticTestTable. If any connectionTesterClassName is explicitly set, the provided ConnectionTester implementation will be used. If preferredTestQuery or automaticTestTable are set, but no connectionTesterClassName is provided, an instance of com.mchange.v2.c3p0.DefaultConnectionTester will be used to perform Connection tests.
If any of these conditions apply, the following section documents how Connection testing with a ConnectionTester works in c3p0.
c3p0 can be configured to test the Connections that it pools in a variety of ways, to minimize the likelihood that your application will see broken or "stale" Connections. Pooled Connections can go bad for a variety of reasons -- some JDBC drivers intentionally "time-out" long-lasting database Connections; back-end databases or networks sometimes go down "stranding" pooled Connections; and Connections can simply become corrupted over time and use due to resource leaks, driver bugs, or other causes.
c3p0 provides users a great deal of flexibility in testing Connections, via the following configuration parameters:
idleConnectionTestPeriod, testConnectionOnCheckout, and testConnectionOnCheckin control when Connections will be tested. automaticTestTable, connectionTesterClassName, and preferredTestQuery control how they will be tested.
When configuring Connection testing, first try to minimize the cost of each test. If you are using a JDBC driver that you are certain supports the new(ish) jdbc4 API — and if you are using c3p0-0.9.5 or higher! — let your driver handle this for you. jdbc4 Connections include a method called isValid() that should be implemented as a fast, reliable Connection test. By default, c3p0 will use that method if it is present.
However, if your driver does not support this new-ish API, c3p0's default behavior is to test Connections by calling the getTables() method on a Connection's associated DatabaseMetaData object. This has the advantage of being very robust and working with any database, regardless of the database schema. However, a call to DatabaseMetaData.getTables() is often much slower than a simple database query, and using this test may significantly impair your pool's performance.
The simplest way to speed up Connection testing under a JDBC 3 driver (or a pre-0.9.5 version of c3p0) is to define a test query with the preferredTestQuery parameter. Be careful, however. Setting preferredTestQuery will lead to errors as Connection tests fail if the query target table does not exist in your database prior to initialization of your DataSource. Depending on your database and JDBC driver, a table-independent query like SELECT 1 may (or may not) be sufficient to verify the Connection. If a table-independent query is not sufficient, instead of preferredTestQuery, you can set the parameter automaticTestTable. Using the name you provide, c3p0 will create an empty table, and make a simple query against it to test the database.
The most reliable time to test Connections is on check-out. But this is also the most costly choice from a client-performance perspective. Most applications should work quite reliably using a combination of idleConnectionTestPeriod and testConnectionOnCheckin. Both the idle test and the check-in test are performed asynchronously, which can lead to better performance, both perceived and actual.
For some applications, high performance is more important than the risk of an occasional database exception. In its default configuration, c3p0 does no Connection testing at all. Setting a fairly long idleConnectionTestPeriod, and not testing on checkout and check-in at all is an excellent, high-performance approach.
It is possible to customize how c3p0's DefaultConnectionTester tests when no preferredTestQuery or automaticTestTable are available. Please see Configuring DefaultConnectionTester.isValidTimeout and Configuring DefaultConnectionTester.QuerylessTestRunner.
Advanced users may define any kind of Connection testing they wish, by implementing a ConnectionTester and supplying the fully qualified name of the class as connectionTesterClassName. If you'd like your custom ConnectionTesters to honor and support the preferredTestQuery and automaticTestTable parameters, implement UnifiedConnectionTester, most conveniently by extending AbstractConnectionTester. See the api docs for more information.
If you know you want to use the jdbc4 Connection.isValid() method, but you want to set a timeout, consider writing a trivial extension of IsValidConnectionTester.
See? These really are trivial to write.
If you don't know what to do, try this:
If you know your driver supports the JDBC 4 Connection.isValid(...) method and you are using c3p0-0.9.5 or above, don't set a preferredTestQuery. If your driver does not support this method (or if you are not sure), try SELECT 1 for your preferredTestQuery, if you are running MySQL or Postgres. For other databases, look for suggestions here. Leave automatedTestTable undefined.
Begin by setting testConnectionOnCheckout to true and get your application to run correctly and stably. If you are happy with your application's performance, you can stop here! This is the simplest, most reliable form of Connection-testing, but it does have a client-visible performance cost.
If you'd like to improve performance by eliminating Connection testing from clients' code path:
Set testConnectionOnCheckout to false
Set testConnectionOnCheckin to true
Set idleConnectionTestPeriod to 30, fire up you application and observe. This is a pretty robust setting, all Connections will tested on check-in and every 30 seconds thereafter while in the pool. Your application should experience broken or stale Connections only very rarely, and the pool should recover from a database shutdown and restart quickly. But there is some overhead associated with all that Connection testing.
If database restarts will be rare so quick recovery is not an issue, consider reducing the frequency of tests by idleConnectionTestPeriod to, say, 300, and see whether clients are troubled by stale or broken Connections. If not, stick with 300, or try an even bigger number. Consider setting testConnectionOnCheckin back to false to avoid unnecessary tests on checkin. Alternatively, if your application does encounter bad Connections, consider reducing idleConnectionTestPeriod and set testConnectionOnCheckin back to true. There are no correct or incorrect values for these parameters: you are trading off overhead for reliability in deciding how frequently to test. The exact numbers are not so critical. It's usually easy to find configurations that perform well. It's rarely worth spending time in pursuit of "optimal" values here.
So, when should you stick with simple and reliable (Step 2 above), and when is it worth going for better performance (Step 3)? In general, it depends on how much work clients typically do with Connections once they check them out. If clients usually make complex queries and/or perform multiple operations, adding the extra cost of one fast test per checkout will not much affect performance. But if your application typically checks out a Connection and performs one simple query with it, throwing in an additional test can really slow things down.
That's nice in theory, but often people don't really have a good sense of how much work clients perform on average. The best thing to do is usually to try Step 3, see if it helps (however you measure performance), see if it hurts (is your application troubled by broken Connections? does it recover from database restarts well enough?), and then decide. You can always go back to simple, slow, and robust. Just set testConnectionOnCheckout to true, testConnectionOnCheckin to false, and set idleConnectionTestPeriod to 0.
But do, always, be sure that your tests themselves are performant, either because your JDBC driver supports Connection.isValid(...) or because you have set an efficient preferredTestQuery !!!