[JAVA] Add apache httpclient library to java clients (#10218)

* Add apache java client option

* Add sample apache client config

* Switch serialization library, use time formatter

* Add pom template for apache dependencies

* Add initial implementation of ApiClient using apache

* Add apache api template

Plus switch to TypeReference to handle generic types

* Add support for sending json data

* Generate test stubs with @Ignore

* Add accept header

* Remove unnecessary builder assignments

* Set responseHeaders instance variable

* Switch to general serialize / deserialize functions

* Handle sending url encoded form data

* Split response processing into new method

* Allow requests without body

* Use general HttpResponse interface

If the method doesn't need to close it

* Use clients connection timeout

* Add constructor accepting custom client

* Handle multipart and direct file uploads

* Support file downloading

Based on the implementation in the jersey client

* Handle missing content disposition

* Raise error if body given for an unexpected method

* Use try with resources for response handling

* Remove unused url parameter encode method

* Handle content type parse exception

* Improve response content type handling

Would have had issues with content type headers containing a charset

* Make all set methods return client

* Add basic readme

* Send content type with files

* Set domain and path on cookies

Otherwise they will be excluded from the request

* Use consistent quoting in error messages

* Add generated apache sample

* Add generated docs changes

* update samples

* rename library, update samples, docs

* update readme

Co-authored-by: Harry White <hwhite@atlassian.com>

samples/client/petstore/java/apache-httpclient/build.gradle

@@ -0,0 +1,138 @@
+apply plugin: 'idea'
+apply plugin: 'eclipse'
+
+group = 'org.openapitools'
+version = '1.0.0'
+
+buildscript {
+    repositories {
+        maven { url "https://repo1.maven.org/maven2" }
+        jcenter()
+    }
+    dependencies {
+        classpath 'com.android.tools.build:gradle:2.3.+'
+        classpath 'com.github.dcendents:android-maven-gradle-plugin:1.5'
+    }
+}
+
+repositories {
+    maven { url "https://repo1.maven.org/maven2" }
+    jcenter()
+}
+
+if(hasProperty('target') && target == 'android') {
+
+    apply plugin: 'com.android.library'
+    apply plugin: 'com.github.dcendents.android-maven'
+
+    android {
+        compileSdkVersion 25
+        buildToolsVersion '25.0.2'
+        defaultConfig {
+            minSdkVersion 14
+            targetSdkVersion 25
+        }
+
+        compileOptions {
+            sourceCompatibility JavaVersion.VERSION_1_8
+            targetCompatibility JavaVersion.VERSION_1_8
+        }
+
+        // Rename the aar correctly
+        libraryVariants.all { variant ->
+            variant.outputs.each { output ->
+                def outputFile = output.outputFile
+                if (outputFile != null && outputFile.name.endsWith('.aar')) {
+                    def fileName = "${project.name}-${variant.baseName}-${version}.aar"
+                    output.outputFile = new File(outputFile.parent, fileName)
+                }
+            }
+        }
+
+        dependencies {
+            provided 'javax.annotation:jsr250-api:1.0'
+        }
+    }
+
+    afterEvaluate {
+        android.libraryVariants.all { variant ->
+            def task = project.tasks.create "jar${variant.name.capitalize()}", Jar
+            task.description = "Create jar artifact for ${variant.name}"
+            task.dependsOn variant.javaCompile
+            task.from variant.javaCompile.destinationDir
+            task.destinationDir = project.file("${project.buildDir}/outputs/jar")
+            task.archiveName = "${project.name}-${variant.baseName}-${version}.jar"
+            artifacts.add('archives', task);
+        }
+    }
+
+    task sourcesJar(type: Jar) {
+        from android.sourceSets.main.java.srcDirs
+        classifier = 'sources'
+    }
+
+    artifacts {
+        archives sourcesJar
+    }
+
+} else {
+
+    apply plugin: 'java'
+    apply plugin: 'maven'
+
+    sourceCompatibility = JavaVersion.VERSION_1_8
+    targetCompatibility = JavaVersion.VERSION_1_8
+
+    install {
+        repositories.mavenInstaller {
+            pom.artifactId = 'petstore-apache-httpclient'
+        }
+    }
+
+    task execute(type:JavaExec) {
+       main = System.getProperty('mainClass')
+       classpath = sourceSets.main.runtimeClasspath
+    }
+
+    task sourcesJar(type: Jar, dependsOn: classes) {
+        classifier = 'sources'
+        from sourceSets.main.allSource
+    }
+
+    task javadocJar(type: Jar, dependsOn: javadoc) {
+        classifier = 'javadoc'
+        from javadoc.destinationDir
+    }
+
+    artifacts {
+        archives sourcesJar
+        archives javadocJar
+    }
+}
+
+ext {
+    swagger_annotations_version = "1.5.22"
+    jackson_version = "2.12.1"
+    jackson_databind_version = "2.10.5.1"
+    jackson_databind_nullable_version = "0.2.1"
+    jackson_threetenbp_version = "2.9.10"
+    jersey_version = "1.19.4"
+    jodatime_version = "2.9.9"
+    junit_version = "4.13.1"
+}
+
+dependencies {
+    implementation "io.swagger:swagger-annotations:$swagger_annotations_version"
+    implementation "com.google.code.findbugs:jsr305:3.0.2"
+    implementation "com.sun.jersey:jersey-client:$jersey_version"
+    implementation "com.sun.jersey.contribs:jersey-multipart:$jersey_version"
+    implementation "com.fasterxml.jackson.core:jackson-core:$jackson_version"
+    implementation "com.fasterxml.jackson.core:jackson-annotations:$jackson_version"
+    implementation "com.fasterxml.jackson.core:jackson-databind:$jackson_databind_version"
+    implementation "com.fasterxml.jackson.jaxrs:jackson-jaxrs-json-provider:$jackson_version"
+    implementation "org.openapitools:jackson-databind-nullable:$jackson_databind_nullable_version"
+    implementation "com.fasterxml.jackson.datatype:jackson-datatype-jsr310:$jackson_version"
+    implementation "com.github.joschi.jackson:jackson-datatype-threetenbp:$jackson_threetenbp_version"
+    implementation 'javax.annotation:javax.annotation-api:1.3.2'
+    testImplementation "junit:junit:$junit_version"
+}