Improve examples

tshemsedinov · tshemsedinov · commit dcf14b130694 · 2024-10-31T18:44:09.000+02:00
diff --git a/JavaScript/0-factory.js b/JavaScript/0-factory.js
@@ -0,0 +1,47 @@
+'use strict';
+
+const pool = (factory) => {
+  const instances = new Array(5).fill(null).map(() => factory.create());
+  return (instance) => {
+    if (instance) {
+      instances.push(instance);
+      console.log('Recycle item, count =', instances.length);
+      return null;
+    }
+    const result = instances.pop();
+    console.log('Get from pool, count =', instances.length);
+    return result;
+  };
+};
+
+class Connection {
+  constructor(index) {
+    this.url = `http://10.0.0.1/${index}`;
+  }
+}
+
+class Factory {
+  constructor() {
+    this.index = 0;
+  }
+
+  create() {
+    return new Connection(this.index++);
+  }
+}
+
+/*
+
+const alternativeFactory = (() => {
+  let index = 0;
+  return () => new Connection(`http://10.0.0.1/${index++}`);
+})();
+
+*/
+
+// Usage
+
+const connectionFactory = new Factory();
+const connectionPool = pool(connectionFactory);
+const connection = connectionPool();
+console.log(connection);
diff --git a/JavaScript/1-simple.js b/JavaScript/1-simple.js
@@ -1,34 +1,36 @@
 'use strict';
 
-const pool = (item) => {
-  pool.items = pool.items || new Array(10).fill(new Array(1000).fill(0));
+class Connection {
+  static index = 0;
 
-  if (item) {
-    pool.items.push(item);
-    console.log('Recycle item, count =', pool.items.length);
-    return;
+  constructor(url) {
+    this.url = url;
   }
 
-  const res = pool.items.pop();
-  console.log('Get from pool, count =', pool.items.length);
-  return res;
+  static create() {
+    return new Connection(`http://10.0.0.1/${Connection.index++}`);
+  }
+}
+
+const pool = () => {
+  const instances = new Array(5).fill(null).map(Connection.create);
+  return (instance) => {
+    if (instance) {
+      instances.push(instance);
+      console.log('Recycle item, count =', instances.length);
+      return null;
+    }
+    const result = instances.pop();
+    console.log('Get from pool, count =', instances.length);
+    return result;
+  };
 };
 
 // Usage
 
-const a1 = pool();
-const b1 = a1.map((x, i) => i).reduce((x, y) => x + y);
-console.log(b1);
-
-const a2 = pool();
-const b2 = a2.map((x, i) => i).reduce((x, y) => x + y);
-console.log(b2);
-
-pool(a1);
-pool(a2);
-
-const a3 = pool();
-const b3 = a3.map((x, i) => i).reduce((x, y) => x + y);
-console.log(b3);
+const connectionPool = pool(Connection.create);
 
-pool(a3);
+for (let i = 0; i < 7; i++) {
+  const connection = connectionPool();
+  console.log(connection);
+}
diff --git a/JavaScript/2-drain.js b/JavaScript/2-drain.js
@@ -1,23 +1,36 @@
 'use strict';
 
-const pool = (item) => {
-  pool.items = pool.items || new Array(10).fill(new Array(1000).fill(0));
+const pool = (factory) => {
+  const instances = new Array(5).fill(null).map(factory);
+  return (instance) => {
+    if (instance) {
+      instances.push(instance);
+      console.log('Recycle item, count =', instances.length);
+      return null;
+    }
+    const result = instances.pop() || factory();
+    console.log('Get from pool, count =', instances.length);
+    return result;
+  };
+};
+
+// Usage
+
+class Connection {
+  static index = 0;
 
-  if (item) {
-    pool.items.push(item);
-    console.log('Recycle item, count =', pool.items.length);
-    return;
+  constructor(url) {
+    this.url = url;
   }
-  const res = pool.items.pop() || new Array(1000).fill(0);
 
-  console.log('Get from pool, count =', pool.items.length);
-  return res;
-};
+  static create() {
+    return new Connection(`http://10.0.0.1/${Connection.index++}`);
+  }
+}
 
-// Usage
+const connectionPool = pool(Connection.create);
 
-for (let i = 0; i < 15; i++) {
-  const a1 = pool();
-  const b1 = a1.map((x, i) => i).reduce((x, y) => x + y);
-  console.log(b1);
+for (let i = 0; i < 10; i++) {
+  const connection = connectionPool();
+  console.log(connection);
 }
diff --git a/JavaScript/3-poolify.js b/JavaScript/3-poolify.js
@@ -7,7 +7,7 @@ const poolify = (factory, size) => {
     if (item) {
       items.push(item);
       console.log('Recycle item, count =', items.length);
-      return;
+      return null;
     }
     const res = items.pop() || factory();
 
@@ -18,7 +18,7 @@ const poolify = (factory, size) => {
 
 // Usage
 
-// Factory to allocate 4kb buffer
+// Factory to allocate 32kb buffer
 const buffer = () => new Uint32Array(1024);
 
 // Allocate pool of 10 buffers
diff --git a/JavaScript/4-improved.js b/JavaScript/4-improved.js
@@ -10,7 +10,7 @@ const poolify = (factory, min, norm, max) => {
         items.push(item);
       }
       console.log('Recycle item, count =', items.length);
-      return;
+      return null;
     }
     if (items.length < min) {
       const instances = duplicate(norm - items.length);
diff --git a/JavaScript/5-async.js b/JavaScript/5-async.js
@@ -58,7 +58,7 @@ const next = () => {
     i++;
     if (i < 20) {
       setTimeout(next, i * 10);
-      setTimeout(pool, i * 100, item);
+      setTimeout(() => pool(item), i * 100);
     }
   });
 };
diff --git a/JavaScript/7-buffer.js b/JavaScript/7-buffer.js
@@ -16,7 +16,7 @@ const poolify = (factory, min, norm, max) => {
         length: pool.items.length,
         allocated: pool.allocated,
       });
-      return;
+      return null;
     }
     if (pool.items.length < min) {
       const items = duplicate(norm - pool.items.length);
@@ -37,7 +37,10 @@ const poolify = (factory, min, norm, max) => {
   return Object.assign(pool, { items, allocated: norm });
 };
 
-const factorify = (Category, ...args) => () => new Category(...args);
+const factorify =
+  (Category, ...args) =>
+  () =>
+    new Category(...args);
 
 // Usage
 
diff --git a/JavaScript/b-timeout.js b/JavaScript/b-timeout.js
@@ -88,11 +88,14 @@ class Pool {
   pool.capture().then((x5) => {
     console.log({ x5 });
   });
-  pool.capture().then((x6) => {
-    console.log({ x6 });
-  }).catch((err) => {
-    console.error({ err });
-  });
+  pool
+    .capture()
+    .then((x6) => {
+      console.log({ x6 });
+    })
+    .catch((err) => {
+      console.error({ err });
+    });
 
   pool.release(x2);
   pool.release(x1);

Original file line number	Diff line number	Diff line change
`@@ -10,7 +10,7 @@ const poolify = (factory, min, norm, max) => {`
`10`	`10`	`items.push(item);`
`11`	`11`	`}`
`12`	`12`	`console.log('Recycle item, count =', items.length);`
`13`		`- return;`
	`13`	`+ return null;`
`14`	`14`	`}`
`15`	`15`	`if (items.length < min) {`
`16`	`16`	`const instances = duplicate(norm - items.length);`
Original file line number	Diff line number	Diff line change
`@@ -58,7 +58,7 @@ const next = () => {`
`58`	`58`	`i++;`
`59`	`59`	`if (i < 20) {`
`60`	`60`	`setTimeout(next, i * 10);`
`61`		`- setTimeout(pool, i * 100, item);`
	`61`	`+ setTimeout(() => pool(item), i * 100);`
`62`	`62`	`}`
`63`	`63`	`});`
`64`	`64`	`};`