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The issues of fastjson will be also posted on Alibaba Cloud Developer Community
FASTJSON v2
is an upgrade of the FASTJSON
, with the goal of providing a highly optimized JSON
library for the next ten years.
- Supports the JSON and JSONB Protocols.
- Supports full parsing and partial parsing.
- Supports Java servers and Android Clients, and has big data applications.
- Supports Kotlin https://alibaba.github.io/fastjson2/kotlin_en
- Supports Android 8+
- Supports
Graal Native-Image
- Supports
JSON Schema
https://alibaba.github.io/fastjson2/json_schema_cn
Related Documents:
JSONB
format documentation:
https://alibaba.github.io/fastjson2/jsonb_format_cnFASTJSON v2
's performance has been significantly improved. For the benchmark, see here:
https://github.com/alibaba/fastjson2/wiki/fastjson_benchmark
FASTJSONv2
's groupId is different from versions 1.x
, it is instead com.alibaba.fastjson2
:
Maven
:
<dependency>
<groupId>com.alibaba.fastjson2</groupId>
<artifactId>fastjson2</artifactId>
<version>2.0.53</version>
</dependency>
Gradle
:
dependencies {
implementation 'com.alibaba.fastjson2:fastjson2:2.0.53'
}
Find the latest version of FASTJSONv2
at maven.org.
If you are using fastjson 1.2.x
, you can use the compatibility package. The compatibility package cannot guarantee 100% compatibility. Please test it yourself and report any problems.
Maven
:
<dependency>
<groupId>com.alibaba</groupId>
<artifactId>fastjson</artifactId>
<version>2.0.53</version>
</dependency>
Gradle
:
dependencies {
implementation 'com.alibaba:fastjson:2.0.53'
}
If your project uses kotlin
, you can use the Fastjson-Kotlin
module, and use the characteristics of kotlin
.
Maven
:
<dependency>
<groupId>com.alibaba.fastjson2</groupId>
<artifactId>fastjson2-kotlin</artifactId>
<version>2.0.53</version>
</dependency>
Add standard library(kotlin-stdlib) and reflection library(kotlin-reflect) as appropriate. If the data class is used or the parameters are passed in through constructor, then add reflection library.
<dependency>
<groupId>org.jetbrains.kotlin</groupId>
<artifactId>kotlin-stdlib</artifactId>
<version>${kotlin-version}</version>
</dependency>
<dependency>
<groupId>org.jetbrains.kotlin</groupId>
<artifactId>kotlin-reflect</artifactId>
<version>${kotlin-version}</version>
</dependency>
Kotlin Gradle
:
dependencies {
implementation("com.alibaba.fastjson2:fastjson2-kotlin:2.0.53")
}
dependencies {
implementation("org.jetbrains.kotlin:kotlin-stdlib:$kotlin_version")
implementation("org.jetbrains.kotlin:kotlin-reflect:$kotlin_version")
}
If your project uses a framework such as SpringFramework
, you can use the fastjson-extension
module, please refer to the usage SpringFramework Support.
Maven
:
<dependency>
<groupId>com.alibaba.fastjson2</groupId>
<artifactId>fastjson2-extension</artifactId>
<version>2.0.53</version>
</dependency>
Gradle
:
dependencies {
implementation 'com.alibaba.fastjson2:fastjson2-extension:2.0.53'
}
The package name of fastjson v2
is different from fastjson v1
. It is com.alibaba.fastjson2
. If you used fastjson v1
before, simply change the package name.
Java
:
String text = "...";
JSONObject data = JSON.parseObject(text);
byte[] bytes = ...;
JSONObject data = JSON.parseObject(bytes);
Kotlin
:
import com.alibaba.fastjson2.*
val text = ... // String
val data = text.parseObject()
val bytes = ... // ByteArray
val data = bytes.parseObject() // JSONObject
Java
:
String text = "...";
JSONArray data = JSON.parseArray(text);
Kotlin
:
import com.alibaba.fastjson2.*
val text = ... // String
val data = text.parseArray() // JSONArray
Java
:
String text = "...";
User data = JSON.parseObject(text, User.class);
Kotlin
:
import com.alibaba.fastjson2.*
val text = ... // String
val data = text.to<User>() // User
val data = text.parseObject<User>() // User
Java
:
Object data = "...";
String text = JSON.toJSONString(data);
byte[] text = JSON.toJSONBytes(data);
Kotlin
:
import com.alibaba.fastjson2.*
val data = ... // Any
val text = data.toJSONString() // String
val bytes = data.toJSONByteArray() // ByteArray
String text = "{\"id\": 2,\"name\": \"fastjson2\"}";
JSONObject obj = JSON.parseObject(text);
int id = obj.getIntValue("id");
String name = obj.getString("name");
String text = "[2, \"fastjson2\"]";
JSONArray array = JSON.parseArray(text);
int id = array.getIntValue(0);
String name = array.getString(1);
Java
:
JSONArray array = ...
JSONObject obj = ...
User user = array.getObject(0, User.class);
User user = obj.getObject("key", User.class);
Kotlin
:
val array = ... // JSONArray
val obj = ... // JSONObject
val user = array.to<User>(0)
val user = obj.to<User>("key")
Java
:
JSONArray array = ...
JSONObject obj = ...
User user = obj.toJavaObject(User.class);
List<User> users = array.toJavaList(User.class);
Kotlin
:
val array = ... // JSONArray
val obj = ... // JSONObject
val user = obj.to<User>() // User
val users = array.toList<User>() // List<User>
Java
:
class User {
public int id;
public String name;
}
User user = new User();
user.id = 2;
user.name = "FastJson2";
String text = JSON.toJSONString(user);
byte[] bytes = JSON.toJSONBytes(user);
Kotlin
:
class User(
var id: Int,
var name: String
)
val user = User()
user.id = 2
user.name = "FastJson2"
val text = user.toJSONString() // String
val bytes = user.toJSONByteArray() // ByteArray
Serialization result:
{
"id" : 2,
"name" : "FastJson2"
}
User user = ...;
byte[] bytes = JSONB.toBytes(user);
byte[] bytes = JSONB.toBytes(user, JSONWriter.Feature.BeanToArray);
byte[] bytes = ...
User user = JSONB.parseObject(bytes, User.class);
User user = JSONB.parseObject(bytes, User.class, JSONReader.Feature.SupportBeanArrayMapping);
String text = ...;
JSONPath path = JSONPath.of("$.id"); // Cached for reuse
JSONReader parser = JSONReader.of(text);
Object result = path.extract(parser);
byte[] bytes = ...;
JSONPath path = JSONPath.of("$.id"); // Cached for reuse
JSONReader parser = JSONReader.of(bytes);
Object result = path.extract(parser);
byte[] bytes = ...;
JSONPath path = JSONPath.of("$.id"); // Cached for reuse
JSONReader parser = JSONReader.ofJSONB(bytes); // Use ofJSONB method
Object result = path.extract(parser);