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Resolves checkstyle errors for template-method thread-pool throttling tls tolerant-reader (#1073)

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* Reduces checkstyle errors in template-method

* Reduces checkstyle errors in thread-pool

* Reduces checkstyle errors in throttling

* Reduces checkstyle errors in tls

* Reduces checkstyle errors in tolerant-reader
This commit is contained in:
Anurag Agarwal
2019-11-10 23:15:17 +05:30
committed by Ilkka Seppälä
parent 9c8ad4485b
commit b92eb5229d
23 changed files with 176 additions and 223 deletions
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25
tolerant-reader/src/main/java/com/iluwatar/tolerantreader/App.java
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@ -23,32 +23,29 @@
package com.iluwatar.tolerantreader;
import java.io.IOException;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import java.io.IOException;
/**
*
* Tolerant Reader is an integration pattern that helps creating robust communication systems. The
* idea is to be as tolerant as possible when reading data from another service. This way, when the
* communication schema changes, the readers must not break.
* <p>
* In this example we use Java serialization to write representations of {@link RainbowFish} objects
* to file. {@link RainbowFish} is the initial version which we can easily read and write using
* {@link RainbowFishSerializer} methods. {@link RainbowFish} then evolves to {@link RainbowFishV2}
* and we again write it to file with a method designed to do just that. However, the reader client
* does not know about the new format and still reads with the method designed for V1 schema.
* Fortunately the reading method has been designed with the Tolerant Reader pattern and does not
* break even though {@link RainbowFishV2} has new fields that are serialized.
*
* <p>In this example we use Java serialization to write representations of {@link RainbowFish}
* objects to file. {@link RainbowFish} is the initial version which we can easily read and write
* using {@link RainbowFishSerializer} methods. {@link RainbowFish} then evolves to {@link
* RainbowFishV2} and we again write it to file with a method designed to do just that. However, the
* reader client does not know about the new format and still reads with the method designed for V1
* schema. Fortunately the reading method has been designed with the Tolerant Reader pattern and
* does not break even though {@link RainbowFishV2} has new fields that are serialized.
*/
public class App {
private static final Logger LOGGER = LoggerFactory.getLogger(App.class);
/**
* Program entry point
* Program entry point.
*/
public static void main(String[] args) throws IOException, ClassNotFoundException {
// Write V1
@ -59,8 +56,8 @@ public class App {
// Read V1
var deserializedRainbowFishV1 = RainbowFishSerializer.readV1("fish1.out");
LOGGER.info("deserializedFishV1 name={} age={} length={} weight={}",
deserializedRainbowFishV1.getName(), deserializedRainbowFishV1.getAge(),
deserializedRainbowFishV1.getLengthMeters(), deserializedRainbowFishV1.getWeightTons());
deserializedRainbowFishV1.getName(), deserializedRainbowFishV1.getAge(),
deserializedRainbowFishV1.getLengthMeters(), deserializedRainbowFishV1.getWeightTons());
// Write V2
var fishV2 = new RainbowFishV2("Scar", 5, 12, 15, true, true, true);
LOGGER.info(

6
tolerant-reader/src/main/java/com/iluwatar/tolerantreader/RainbowFish.java
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@ -26,9 +26,7 @@ package com.iluwatar.tolerantreader;
import java.io.Serializable;
/**
*
* RainbowFish is the initial schema
*
* RainbowFish is the initial schema.
*/
public class RainbowFish implements Serializable {
@ -40,7 +38,7 @@ public class RainbowFish implements Serializable {
private int weightTons;
/**
* Constructor
* Constructor.
*/
public RainbowFish(String name, int age, int lengthMeters, int weightTons) {
this.name = name;

46
tolerant-reader/src/main/java/com/iluwatar/tolerantreader/RainbowFishSerializer.java
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@ -28,16 +28,13 @@ import java.io.FileOutputStream;
import java.io.IOException;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
import java.util.HashMap;
import java.util.Map;
/**
*
* RainbowFishSerializer provides methods for reading and writing {@link RainbowFish} objects to
* file. Tolerant Reader pattern is implemented here by serializing maps instead of
* {@link RainbowFish} objects. This way the reader does not break even though new properties are
* added to the schema.
*
* file. Tolerant Reader pattern is implemented here by serializing maps instead of {@link
* RainbowFish} objects. This way the reader does not break even though new properties are added to
* the schema.
*/
public final class RainbowFishSerializer {
@ -45,54 +42,55 @@ public final class RainbowFishSerializer {
}
/**
* Write V1 RainbowFish to file
* Write V1 RainbowFish to file.
*/
public static void writeV1(RainbowFish rainbowFish, String filename) throws IOException {
var map = Map.of(
"name", rainbowFish.getName(),
"age", String.format("%d", rainbowFish.getAge()),
"lengthMeters", String.format("%d", rainbowFish.getLengthMeters()),
"weightTons", String.format("%d", rainbowFish.getWeightTons())
"name", rainbowFish.getName(),
"age", String.format("%d", rainbowFish.getAge()),
"lengthMeters", String.format("%d", rainbowFish.getLengthMeters()),
"weightTons", String.format("%d", rainbowFish.getWeightTons())
);
try (var fileOut = new FileOutputStream(filename);
var objOut = new ObjectOutputStream(fileOut)) {
var objOut = new ObjectOutputStream(fileOut)) {
objOut.writeObject(map);
}
}
/**
* Write V2 RainbowFish to file
* Write V2 RainbowFish to file.
*/
public static void writeV2(RainbowFishV2 rainbowFish, String filename) throws IOException {
var map = Map.of(
"name", rainbowFish.getName(),
"age", String.format("%d", rainbowFish.getAge()),
"lengthMeters", String.format("%d", rainbowFish.getLengthMeters()),
"weightTons", String.format("%d", rainbowFish.getWeightTons()),
"angry", Boolean.toString(rainbowFish.getAngry()),
"hungry", Boolean.toString(rainbowFish.getHungry()),
"sleeping", Boolean.toString(rainbowFish.getSleeping())
"name", rainbowFish.getName(),
"age", String.format("%d", rainbowFish.getAge()),
"lengthMeters", String.format("%d", rainbowFish.getLengthMeters()),
"weightTons", String.format("%d", rainbowFish.getWeightTons()),
"angry", Boolean.toString(rainbowFish.getAngry()),
"hungry", Boolean.toString(rainbowFish.getHungry()),
"sleeping", Boolean.toString(rainbowFish.getSleeping())
);
try (var fileOut = new FileOutputStream(filename);
var objOut = new ObjectOutputStream(fileOut)) {
var objOut = new ObjectOutputStream(fileOut)) {
objOut.writeObject(map);
}
}
/**
* Read V1 RainbowFish from file
* Read V1 RainbowFish from file.
*/
public static RainbowFish readV1(String filename) throws IOException, ClassNotFoundException {
Map<String, String> map = null;
try (var fileIn = new FileInputStream(filename);
var objIn = new ObjectInputStream(fileIn)) {
var objIn = new ObjectInputStream(fileIn)) {
map = (Map<String, String>) objIn.readObject();
}
return new RainbowFish(map.get("name"), Integer.parseInt(map.get("age")), Integer.parseInt(map.get("lengthMeters")),
return new RainbowFish(map.get("name"), Integer.parseInt(map.get("age")), Integer
.parseInt(map.get("lengthMeters")),
Integer.parseInt(map.get("weightTons")));
}
}

8
tolerant-reader/src/main/java/com/iluwatar/tolerantreader/RainbowFishV2.java
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@ -24,9 +24,7 @@
package com.iluwatar.tolerantreader;
/**
*
* RainbowFishV2 is the evolved schema
*
* RainbowFishV2 is the evolved schema.
*/
public class RainbowFishV2 extends RainbowFish {
@ -41,10 +39,10 @@ public class RainbowFishV2 extends RainbowFish {
}
/**
* Constructor
* Constructor.
*/
public RainbowFishV2(String name, int age, int lengthMeters, int weightTons, boolean sleeping,
boolean hungry, boolean angry) {
boolean hungry, boolean angry) {
this(name, age, lengthMeters, weightTons);
this.sleeping = sleeping;
this.hungry = hungry;