BAEL-3091: The Prototype Pattern in Java (changed code based on valid comments from a reader)

core-kotlin-io/src/main/kotlin/com/baeldung/inputstream/InputStreamExtension.kt

@@ -0,0 +1,18 @@
+package com.baeldung.inputstream
+
+import java.io.InputStream
+
+fun InputStream.readUpToChar(stopChar: Char): String {
+    val stringBuilder = StringBuilder()
+    var currentChar = this.read().toChar()
+    while (currentChar != stopChar) {
+        stringBuilder.append(currentChar)
+        currentChar = this.read().toChar()
+        if (this.available() <= 0) {
+            stringBuilder.append(currentChar)
+            break
+        }
+    }
+    return stringBuilder.toString()
+}
+

core-kotlin-io/src/test/kotlin/com/baeldung/console/ConsoleIOUnitTest.kt

@@ -0,0 +1,79 @@
+package com.baeldung.console
+
+import org.assertj.core.api.Assertions.assertThat
+import org.junit.jupiter.api.AfterEach
+import org.junit.jupiter.api.Test
+import org.mockito.Mockito.`when`
+import org.mockito.Mockito.mock
+import java.io.BufferedReader
+import java.io.ByteArrayInputStream
+import java.io.ByteArrayOutputStream
+import java.io.Console
+import java.io.InputStreamReader
+import java.io.PrintStream
+import java.util.*
+
+
+class ConsoleIOUnitTest {
+
+    @Test
+    fun givenText_whenPrint_thenPrintText() {
+        val expectedTest = "Hello from Kotlin"
+        val out = ByteArrayOutputStream()
+        System.setOut(PrintStream(out))
+
+        print(expectedTest)
+        out.flush()
+        val printedText = String(out.toByteArray())
+
+        assertThat(printedText).isEqualTo(expectedTest)
+    }
+
+    @Test
+    fun givenInput_whenRead_thenReadText() {
+        val expectedTest = "Hello from Kotlin"
+        val input = ByteArrayInputStream(expectedTest.toByteArray())
+        System.setIn(input)
+
+        val readText = readLine()
+
+        assertThat(readText).isEqualTo(expectedTest)
+    }
+
+    @Test
+    fun givenInput_whenReadWithScanner_thenReadText() {
+        val expectedTest = "Hello from Kotlin"
+        val scanner = Scanner(ByteArrayInputStream(expectedTest.toByteArray()))
+
+        val readText = scanner.nextLine()
+
+        assertThat(readText).isEqualTo(expectedTest)
+    }
+
+    @Test
+    fun givenInput_whenReadWithBufferedReader_thenReadText() {
+        val expectedTest = "Hello from Kotlin"
+        val reader = BufferedReader(InputStreamReader(ByteArrayInputStream(expectedTest.toByteArray())))
+
+        val readText = reader.readLine()
+
+        assertThat(readText).isEqualTo(expectedTest)
+    }
+
+    @Test
+    fun givenInput_whenReadWithConsole_thenReadText() {
+        val expectedTest = "Hello from Kotlin"
+        val console = mock(Console::class.java)
+        `when`(console.readLine()).thenReturn(expectedTest)
+
+        val readText = console.readLine()
+
+        assertThat(readText).isEqualTo(expectedTest)
+    }
+
+    @AfterEach
+    fun resetIO() {
+        System.setOut(System.out)
+        System.setIn(System.`in`)
+    }
+}

core-kotlin-io/src/test/kotlin/com/baeldung/inputstream/InputStreamToStringTest.kt

@@ -0,0 +1,72 @@
+package com.baeldung.inputstream
+
+import kotlinx.io.core.use
+import org.junit.Test
+import java.io.BufferedReader
+import java.io.File
+import kotlin.test.assertEquals
+
+class InputStreamToStringTest {
+    private val fileName = "src/test/resources/inputstream2string.txt"
+    private val endOfLine = System.lineSeparator()
+    private val fileFullContent = "Computer programming can be a hassle$endOfLine" +
+            "It's like trying to take a defended castle"
+
+    @Test
+    fun whenReadFileWithBufferedReader_thenFullFileContentIsReadAsString() {
+        val file = File(fileName)
+        val inputStream = file.inputStream()
+        val content = inputStream.bufferedReader().use(BufferedReader::readText)
+        assertEquals(fileFullContent, content)
+    }
+    @Test
+    fun whenReadFileWithBufferedReaderReadText_thenFullFileContentIsReadAsString() {
+        val file = File(fileName)
+        val inputStream = file.inputStream()
+        val reader = BufferedReader(inputStream.reader())
+        var content: String
+        try {
+            content = reader.readText()
+        } finally {
+            reader.close()
+        }
+        assertEquals(fileFullContent, content)
+    }
+    @Test
+    fun whenReadFileWithBufferedReaderManually_thenFullFileContentIsReadAsString() {
+        val file = File(fileName)
+        val inputStream = file.inputStream()
+        val reader = BufferedReader(inputStream.reader())
+        val content = StringBuilder()
+        try {
+            var line = reader.readLine()
+            while (line != null) {
+                content.append(line)
+                line = reader.readLine()
+            }
+        } finally {
+            reader.close()
+        }
+        assertEquals(fileFullContent.replace(endOfLine, ""), content.toString())
+
+    }
+
+    @Test
+    fun whenReadFileUpToStopChar_thenPartBeforeStopCharIsReadAsString() {
+        val file = File(fileName)
+        val inputStream = file.inputStream()
+        val content = inputStream.use { it.readUpToChar(' ') }
+        assertEquals("Computer", content)
+    }
+
+    @Test
+    fun whenReadFileWithoutContainingStopChar_thenFullFileContentIsReadAsString() {
+        val file = File(fileName)
+        val inputStream = file.inputStream()
+        val content = inputStream.use { it.readUpToChar('-') }
+        assertEquals(fileFullContent, content)
+    }
+
+
+}
+

core-kotlin-io/src/test/resources/inputstream2string.txt

@@ -0,0 +1,2 @@
+Computer programming can be a hassle
+It's like trying to take a defended castle

core-kotlin-io/src/test/resources/mockito-extensions/org.mockito.plugins.MockMaker

@@ -0,0 +1 @@
+mock-maker-inline