Android extensions for Apache HttpClient 5.0.x

Dependency management

Add API or implementation dependency on com.github.ok2c.hc5.android:httpclient-android to Gradle dependencies. This will automatically introduce transitive dependency on Apache HttpClient.

dependencies {
    api 'com.github.ok2c.hc5.android:httpclient-android:0.3.0'
}

Configuration and application

HttpClient 5.0 is compatible with Android API 19 or later without any modifications

Generally it is strongly advised to use a single instance of CloseableHttpClient per Android activity or several related activities. It may also be a good idea to close out idle connections on activity pause and evict expired connections upon activity resumption.

Activities that have a dedicated CloseableHttpClient instance should close it when destroyed in order to deallocate system resources held by persistent HTTP connections kept alive in the connection pool.

HttpClientActivity provided by the library can be used as a base class for all activities that involve HTTP communication using Apache HttpClient.

abstract class HttpClientActivity(builder: PoolingHttpClientConnectionManagerBuilder): Activity() {

    protected var connectionManager: PoolingHttpClientConnectionManager = builder.build()

    override fun onPause() {
        connectionManager.closeIdle(TimeValue.ZERO_MILLISECONDS)
        super.onPause()
    }

    override fun onResume() {
        connectionManager.closeExpired()
        super.onResume()
    }

    override fun onStop() {
        connectionManager.closeIdle(TimeValue.ZERO_MILLISECONDS)
        super.onStop()
    }

    override fun onDestroy() {
        connectionManager.close(CloseMode.GRACEFUL)
        super.onDestroy()
    }

}

Logging

Apache HttpClient 5.0 uses SLF4J APIs to log messages. Any SLF4J backend compatible with Android should work with HttpClient.

This library however ships with its own simple SLF4J logger implementation that redirects all log events to Android Logcat. What differs this implementation from several similar ones is that groups all HttpClient related events into a single category with the tag HttpClient. Wire log events are redirected to HttpClientWire and message header events to HttpClientHeader.

1. Add the following class to application code. IMPORTANT Please note this class must be located in the org.slf4j.impl package.

package org.slf4j.impl

import com.ok2c.hc.android.logging.AndroidLoggerFactory
import org.slf4j.ILoggerFactory
import org.slf4j.spi.LoggerFactoryBinder

class StaticLoggerBinder: LoggerFactoryBinder {

   companion object {
      private val INSTANCE = StaticLoggerBinder()

      @JvmStatic
      fun getSingleton(): StaticLoggerBinder? {
         return INSTANCE
      }
   }

    override fun getLoggerFactory(): ILoggerFactory? {
        return AndroidLoggerFactory.INSTANCE
    }

    override fun getLoggerFactoryClassStr(): String? {
        return AndroidLoggerFactory::class.java.name
    }

}

1. Activate Logcat categories

    adb shell setprop log.tag.HttpClient VERBOSE
    adb shell setprop log.tag.HttpClientHeader VERBOSE
    adb shell setprop log.tag.HttpClientWire VERBOSE
       
   

   Skip HttpClientWire if wire logging is not required.