How to improve build times in android

Few steps that can be taken to improve the build performance Use Gradle enterprise caching to preserve build artifacts between runs Split into library Modules Breaking up appLibrary into their respective library modules Integrate Pipe line Development build pipeline - run for each PR Release build pipeline - run for release cycle Integrte Sonar Profiling

Android application security best practices:

Provide security for android applications by applying security best practices and techniques.

The common security issues may arise from different ways:

Attack vector :

Technique that a hacker uses to gain access to another computing device or network in order to inject a “bad code” often called payloads. This vector helps hackers to exploit system vulnerabilities.

Identify application based permissions data protection:

Week Server side implementation:

Threat to data:

SQL Injection:

Cross Site Scripting (XSS):

How to scale an image to fix mobile screen

public static Image scaleImage(Image original, int newWidth, int newHeight) {
int[] rawInput = new int[original.getHeight() * original.getWidth()];
original.getRGB(rawInput, 0, original.getWidth(), 0, 0, original.getWidth(), original.getHeight());

int[] rawOutput = new int[newWidth * newHeight];

// YD compensates for the x loop by subtracting the width back out
int YD = (original.getHeight() / newHeight) * original.getWidth() - original.getWidth();
int YR = original.getHeight() % newHeight;
int XD = original.getWidth() / newWidth;
int XR = original.getWidth() % newWidth;
int outOffset = 0;
int inOffset = 0;

for (int y = newHeight, YE = 0; y > 0; y--) {
for (int x = newWidth, XE = 0; x > 0; x--) {
rawOutput[outOffset++] = rawInput[inOffset];
inOffset += XD;
XE += XR;
if (XE >= newWidth) {
XE -= newWidth;
inOffset++;
}
}
inOffset += YD;
YE += YR;
if (YE >= newHeight) {
YE -= newHeight;
inOffset += original.getWidth();
}
}
return Image.createRGBImage(rawOutput, newWidth, newHeight, false);
}

contact number from phone book : using j2me

public static Vector retrieveContactInfo()
{
Vector vContactInfo = new Vector();

//Check that PIM Optional Package is available
String pimVersion = System.getProperty("microedition.pim.version");
if(pimVersion == null)
return null;
else
{
PIM pim = PIM.getInstance();
ContactList contactList = null;
try
{
contactList = (ContactList) pim.openPIMList(PIM.CONTACT_LIST, PIM.READ_ONLY);
if(contactList == null)
{
return null;
}

Enumeration clEnum = contactList.items();
while(clEnum.hasMoreElements())
{
Contact contact = (Contact) clEnum.nextElement();
String name = "";

try
{
//if(contactList.isSupportedField(Contact.FORMATTED_NAME))
{
name = contact.getString(Contact.FORMATTED_NAME, 0);
}
}
catch(Exception ex) //An unexpected error occurred while reading the contact name.
{
continue;
}

if(!contactList.isSupportedField(Contact.TEL))
{
continue;
}

int noOfPhones = contact.countValues(Contact.TEL);
Vector vTelInfo = new Vector();
for(int i = 0; i < contactattribute =" contact.getAttributes(Contact.TEL," number =" contact.getString(Contact.TEL," teltype = "" contactattribute ="="" teltype = "Home" contactattribute ="="" teltype = "Mobile" contactattribute ="="" teltype = "Work" contactattribute ="="" teltype = "Other" contactattribute ="="" teltype = "Pager" contactattribute ="="" teltype = "General"> 0)
{
vContactInfo.addElement(new ContactInfo(name, vTelInfo));
}
}
}
catch (PIMException ex)
{
return null;
}
catch (SecurityException ex)
{
return null;
}

return vContactInfo;
}

String manipulation, split string with specified delimeter and store into vector

public class StringManip {

public static Vector split(String str, final String delim, boolean discardEndData) {
Vector vComponents = new Vector();
int index = 0;

while (index < str.length()) {
int newIndex = str.indexOf(delim, index);
if (newIndex > 0) {
vComponents.addElement(str.substring(index, newIndex));
} else {
if (discardEndData == false) {
vComponents.addElement(str.substring(index));
}
break;
}

index = newIndex + delim.length();
}

return vComponents;
}

example :-
Vector v = StringManip.split("aaa,aaaa,aaa,aa" , ",", false);

J2me source code to find the screen size to work the application in different screen size

import com.sun.lwuit.Display;

/**
* This class enumerates the different phone resolution categories.
* Note that enums are not supported in source 1.3.
* @author Sirajuddin
*/

public abstract class PhoneDisplay {

public static int LOWRES = 0;
public static int MEDRES = 1;
public static int HIGHRES = 2;

public static int getCategory(Display display)
{
int width = display.getDisplayWidth();
int height = display.getDisplayHeight();

int diagonal = (int) Math.sqrt((width * width) + (height * height));

if(diagonal < 205)
return LOWRES;

return HIGHRES;
}
};