RealmExpressions
Build strings expressions and transform it to Realm objects.
Installation
- Add it in your root build.gradle at the end of repositories
allprojects {
repositories {
...
maven { url 'https://jitpack.io' }
}
}
- Add the dependency
dependencies {
implementation 'com.github.javierpe:RealmExpressions:1.0.3'
}
Usage
- RealmExpression instance
RealmExpression.init(context);
- Build engine
RealmExpression engine = new RealmExpression.Builder().addExpression(KEY, EXPRESSION);
- Add template (Optional)
RealmExpression engine = new RealmExpression.Builder()
.addExpression(KEY, EXPRESSION)
.withTemplate("Result: KEY");
Evaluation
- Synchronous evaluation
Object result = engine.evaluateSync();
- Asynchronous evaluation
engine.evaluateAsync(new OnEvaluationListener() {
@Override
public void onEvaluationResult(String template, Object result) {
System.out.println("Template: " + template);
System.out.println("Result: " + result);
System.out.println("* * * * * * * * * * *");
}
@Override
public void onExpressionResult(String key, String expression, Object result) {
System.out.println("Key: " + key);
System.out.println("Expression: " + expression);
System.out.println("Result: " + result);
System.out.println("= = = = = = = = = = = =");
}
@Override
public void onError(String key, String expression, Throwable throwable) {
// Some error in expression..
}
});
Environments
You can add environments objects or Realm models so you can use them later
RealmExpression.addEnvironmentObject("user", User.getCurrentUser(), isDisposable);
Example: engine.addExpression("A", "user.@getLastName()");
isDisposable allows you to discard the object when necessary.
Native classes
A native class is not a RealmObejct and can be accessed from whatever expression. RealmExpression has default native classes
DateNative accessed from @@date.
Methods
| Access | Return | Params | Description | Example |
|---|---|---|---|---|
.@now() | String date | Not support | Get the current date | @@date.@now() |
DeviceNative accessed from @@device.
Methods
| Access | Return | Params | Description | Example |
|---|---|---|---|---|
.@randomUUID() | String UUID | Not support | Get random UUID | @@device.@randomUUID() |
.@imei() | String IMEI | Not support | Get random UUID (Permission required since Android 6.0 Marshmallow) | @@device.@imei() |
.@androidVersion() | String Android version | Not support | Get Android Version from Build.VERSION.RELEASE | @@device.@androidVersion() |
.@appVersion() | String app version | Not support | Get app version name | @@device.@appVersion() |
.@lastLocation() | String location | Not support | Get last know location with format 19.0460714,-98.2267667 | @@device.@lastLocation() |
Create native class
You can create a native class extends by NativeClass and access it by you custom key. To add this class it is necessary call to RealmExpression.addNewNativeClass(KEY, NativeClass);
Others instance methods
| Code | Description |
|---|---|
RealmExpression.dispose(); | Discard all no disposable environment objects |
RealmExpression.disposeAll() | Remove all environment objects |
RealmExpression.removeEnvironment(KEY); | Removes an specific environment |
RealmExpression.removeNativeClass(KEY); | Removes an specific NativeClass |
Please start now! 😬
Write an expression
| Sintax | Example | Description |
|---|---|---|
@@ | @@device.@androidVersion() | For reserved words |
$_realmClass | $_client.@byId(...) | For Realm method class |
$envObjectName | $client.@getName() | For Realm Objects |
2*5/10 | 2*5/10 | For simple math operation |
@REUSE(objectName.@getName()) | @REUSE(B1.@getName()) | Where B1 is instance of 'client' |
Examples
RealmExpression.addEnvironmentObject("user", KUser.getCurrentUser(), false);
RealmExpression engine = new RealmExpression.Builder()
.addExpression("B1", "$user.@getFirstName()")
.withTemplate("NAME: B1");
engine.evaluateAsync(new OnEvaluationListener() {
@Override
public void onEvaluationResult(String template, Object result) {
System.out.println("Template: " + template);
System.out.println("Result: " + result);
System.out.println("* * * * * * * * * * *");
}
@Override
public void onExpressionResult(String key, String expression, Object result) {
System.out.println("Key: " + key);
System.out.println("Expression: " + expression);
System.out.println("Result: " + result);
System.out.println("= = = = = = = = = = = =");
}
@Override
public void onError(String key, String expression, Throwable throwable) {
}
});
Output
NAME: Jhon
Love build this
License
Copyright 2018 javierpe
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.