tech.sirwellington.alchemy.http.HttpResponse Maven / Gradle / Ivy
Go to download
Show more of this group Show more artifacts with this name
Show all versions of alchemy-http Show documentation
Show all versions of alchemy-http Show documentation
Part of the Alchemy Collection.
REST without the MESS.
Makes it dead-easy to call RESTful Web Services in Java.
It is designed for interactions with APIs written in REST and JSON.
/*
* Copyright 2015 SirWellington Tech.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package tech.sirwellington.alchemy.http;
import com.google.gson.Gson;
import com.google.gson.GsonBuilder;
import com.google.gson.JsonElement;
import com.google.gson.JsonNull;
import com.google.gson.JsonParseException;
import java.lang.reflect.Array;
import java.util.Arrays;
import java.util.Collections;
import java.util.List;
import java.util.Map;
import java.util.Objects;
import jdk.nashorn.internal.ir.annotations.Immutable;
import tech.sirwellington.alchemy.annotations.arguments.Nullable;
import tech.sirwellington.alchemy.annotations.designs.patterns.BuilderPattern;
import tech.sirwellington.alchemy.http.exceptions.JsonException;
import static java.util.Collections.unmodifiableMap;
import static tech.sirwellington.alchemy.annotations.designs.patterns.BuilderPattern.Role.BUILDER;
import static tech.sirwellington.alchemy.annotations.designs.patterns.BuilderPattern.Role.PRODUCT;
import static tech.sirwellington.alchemy.arguments.Arguments.checkThat;
import static tech.sirwellington.alchemy.arguments.assertions.Assertions.notNull;
import static tech.sirwellington.alchemy.http.HttpAssertions.validHttpStatusCode;
import static tech.sirwellington.alchemy.http.HttpAssertions.validResponseClass;
/**
*
* @see HttpResponse.Builder
*
* @author SirWellington
*/
@Immutable
public interface HttpResponse
{
/**
* @return The HTTP Status code of the request.
*/
int statusCode();
/**
* HTTP OK are 200-208 or the 226 status code.
*
* @return true if the status code is "OK", false otherwise.
*
* @see
* https://en.wikipedia.org/wiki/List_of_HTTP_status_codes#2xx_Success
*/
default boolean isOk()
{
int statusCode = statusCode();
//Valid HTTP "OK" level Status Codes
return (statusCode >= 200 && statusCode <= 208) || statusCode == 226;
}
/**
* @return The response headers returned by the REST Service.
*/
@Nullable
Map responseHeaders();
/**
* Get the Response Body as a String.
*
* @return The Response Body as a String
*/
String bodyAsString();
/**
* Get the Response Body in JSON format.
*
* @return The JSON Response Body
*
* @throws JsonException
*/
JsonElement body() throws JsonException;
/**
* Get the Response Body as a custom POJO Type. (Plain Old Java Object) Ensure that the POJO is styled in typical
* Java Bean/Value object style. Getters and setters are not required, although {@link Object#hashCode() }
* and {@link Object#equals(java.lang.Object)} is recommended for any value type.
*
* @param The type of the POJO
* @param classOfT The Class of the POJO.
*
* @return An instance of {@code T}, mapped from the JSON Body.
*
* @throws JsonException If the {@linkplain #body() JSON Body} could not be parsed.
*/
T bodyAs(Class classOfT) throws JsonException;
/**
* Use in cases where you expect the {@linkplain #body() Response Body} to be a JSON Array. A {@link List} is
* returned instead of an Array.
*
* @param The type of the POJO
* @param classOfT The Class of the POJO.
*
* @return A List of T, parse from the JSON Body.
*
* @throws JsonException
*/
List bodyAsArrayOf(Class classOfT) throws JsonException;
default boolean equals(HttpResponse other)
{
if (other == null)
{
return false;
}
if (this.statusCode() != other.statusCode())
{
return false;
}
if (!Objects.equals(this.responseHeaders(), other.responseHeaders()))
{
return false;
}
if (!Objects.equals(this.bodyAsString(), other.bodyAsString()))
{
return false;
}
return true;
}
static Builder builder()
{
return Builder.newInstance();
}
//==============================================================================================
// Builder Implementation
//==============================================================================================
@BuilderPattern(role = BUILDER)
static class Builder
{
//Start negative to make sure that status code was set
private int statusCode = -100;
private Map responseHeaders = Collections.emptyMap();
private Gson gson = new GsonBuilder()
.setDateFormat(Constants.DATE_FORMAT)
.create();
private JsonElement responseBody = JsonNull.INSTANCE;
public static Builder newInstance()
{
return new Builder();
}
public Builder mergeFrom(HttpResponse other)
{
checkThat(other).is(notNull());
return this.withResponseBody(other.body())
.withStatusCode(other.statusCode())
.withResponseHeaders(other.responseHeaders());
}
public Builder withStatusCode(int statusCode) throws IllegalArgumentException
{
//TODO: Also add check that status code is in the HTTP Range
checkThat(statusCode).is(validHttpStatusCode());
this.statusCode = statusCode;
return this;
}
public Builder withResponseHeaders(Map responseHeaders) throws IllegalArgumentException
{
if (responseHeaders == null)
{
responseHeaders = Collections.emptyMap();
}
this.responseHeaders = responseHeaders;
return this;
}
public Builder withResponseBody(JsonElement json) throws IllegalArgumentException
{
checkThat(json).is(notNull());
this.responseBody = json;
return this;
}
public Builder usingGson(Gson gson) throws IllegalArgumentException
{
checkThat(gson).is(notNull());
this.gson = gson;
return this;
}
public HttpResponse build() throws IllegalStateException
{
checkThat(statusCode)
.throwing(ex -> new IllegalStateException("No status code supplied"))
.is(validHttpStatusCode());
checkThat(responseBody)
.usingMessage("missing Response Body")
.is(notNull());
return new Impl(statusCode,
unmodifiableMap(responseHeaders),
gson,
responseBody);
}
//==============================================================================================
// Implementation
//==============================================================================================
@Immutable
@BuilderPattern(role = PRODUCT)
private static class Impl implements HttpResponse
{
private final int statusCode;
private final Map responseHeaders;
private final Gson gson;
private final JsonElement responseBody;
private Impl(int statusCode,
Map responseHeaders,
Gson gson,
JsonElement response)
{
this.statusCode = statusCode;
this.responseHeaders = responseHeaders;
this.gson = gson;
this.responseBody = response;
}
@Override
public int statusCode()
{
return statusCode;
}
@Override
public Map responseHeaders()
{
return responseHeaders;
}
@Override
public String bodyAsString()
{
if (responseBody.isJsonPrimitive())
{
return responseBody.getAsString();
}
else
{
return responseBody.toString();
}
}
@Override
public JsonElement body() throws JsonParseException
{
JsonElement copy = gson.toJsonTree(responseBody);
return copy;
}
@Override
public T bodyAs(Class classOfT) throws JsonParseException
{
checkThat(classOfT).is(validResponseClass());
try
{
T instance = gson.fromJson(responseBody, classOfT);
return instance;
}
catch (Exception ex)
{
throw new JsonException("Failed to parse json to class: " + classOfT, ex);
}
}
@Override
public List bodyAsArrayOf(Class classOfT) throws JsonException
{
checkThat(classOfT).is(validResponseClass());
T[] array = (T[]) Array.newInstance(classOfT, 0);
Class arrayClass = (Class) array.getClass();
try
{
array = gson.fromJson(responseBody, arrayClass);
return array == null ? Collections.emptyList() : Arrays.asList(array);
}
catch (Exception ex)
{
throw new JsonException("Failed to parse json to class: " + classOfT, ex);
}
}
@Override
public int hashCode()
{
int hash = 3;
hash = 41 * hash + this.statusCode;
hash = 41 * hash + Objects.hashCode(this.responseHeaders);
hash = 41 * hash + Objects.hashCode(this.responseBody);
return hash;
}
@Override
public boolean equals(Object obj)
{
if (obj == null)
{
return false;
}
if (!(obj instanceof HttpResponse))
{
return false;
}
return this.equals((HttpResponse) obj);
}
@Override
public String toString()
{
return "HttpResponse{" + "statusCode=" + statusCode + ", responseHeaders=" + responseHeaders + ", response=" + responseBody + '}';
}
}
}
}
© 2015 - 2025 Weber Informatics LLC | Privacy Policy