Merge pull request #15 from embulk/pr/06-add-checkstyle

Checkstyle with checkstyle 9.3

build.gradle

@@ -3,6 +3,7 @@ plugins {
     id "maven-publish"
     id "signing"
     alias(libs.plugins.gradle.embulk.plugins)
+    id "checkstyle"
 }
 repositories {
     mavenCentral()
@@ -169,3 +170,13 @@ test {
         outputs.upToDateWhen { false }
     }
 }
+
+checkstyle {
+    toolVersion = libs.versions.checkstyle.get()
+    configFile = file("${rootProject.projectDir}/config/checkstyle/checkstyle.xml")
+    configProperties = [
+            "org.checkstyle.google.suppressionfilter.config": file("${rootProject.projectDir}/config/checkstyle/checkstyle-suppressions.xml"),
+    ]
+    ignoreFailures = false
+    maxWarnings = 0
+}

config/checkstyle/README.md

@@ -0,0 +1,11 @@
+Checkstyle for the Embulk project
+==================================
+
+* google_check.xml: Downloaded from: https://github.com/checkstyle/checkstyle/blob/checkstyle-9.3/src/main/resources/google_checks.xml
+     * Commit: 5c1903792f8432243cc8ae5cd79a03a004d3c09c
+* checkstyle.xml: Customized from google_check.xml.
+    * To enable suppressions through checkstyle-suppressions.xml.
+    * To enable suppressions with @SuppressWarnings.
+    * To indent with 4-column spaces.
+    * To limit columns to 180 characters.
+    * To reject unused imports.

config/checkstyle/checkstyle-suppressions.xml

@@ -0,0 +1,14 @@
+<?xml version="1.0"?>
+
+<!DOCTYPE suppressions PUBLIC
+    "-//Puppy Crawl//DTD Suppressions 1.2//EN"
+    "http://checkstyle.sourceforge.net/dtds/suppressions_1_2.dtd">
+
+<suppressions>
+  <suppress checks="JavadocMethod" files=".*"/>
+  <suppress checks="JavadocParagraph" files=".*"/>
+  <suppress checks="JavadocTagContinuationIndentation" files=".*"/>
+  <suppress checks="MissingJavadocType" files=".*"/>
+  <suppress checks="SingleLineJavadoc" files=".*"/>
+  <suppress checks="SummaryJavadoc" files=".*"/>
+</suppressions>

gradle/libs.versions.toml

@@ -18,6 +18,8 @@ jackson = "2.16.2"
 
 junit4 = "4.13.2"
 
+checkstyle = "9.3"
+
 [libraries]
 
 embulk-core = { group = "org.embulk", name = "embulk-core", version.ref = "embulk-core" }

src/main/java/org/embulk/input/CommandFileInputPlugin.java

@@ -1,36 +1,34 @@
 package org.embulk.input;
 
+import java.io.FilterInputStream;
+import java.io.IOException;
+import java.io.InputStream;
+import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.Collections;
 import java.util.List;
-import java.util.ArrayList;
-import java.io.InputStream;
-import java.io.IOException;
-import java.io.FilterInputStream;
-import org.slf4j.Logger;
+import org.embulk.config.ConfigDiff;
+import org.embulk.config.ConfigException;
+import org.embulk.config.ConfigSource;
 import org.embulk.config.TaskReport;
+import org.embulk.config.TaskSource;
+import org.embulk.spi.Exec;
+import org.embulk.spi.FileInputPlugin;
+import org.embulk.spi.TransactionalFileInput;
 import org.embulk.util.config.Config;
 import org.embulk.util.config.ConfigDefault;
 import org.embulk.util.config.ConfigMapper;
 import org.embulk.util.config.ConfigMapperFactory;
 import org.embulk.util.config.Task;
 import org.embulk.util.config.TaskMapper;
-import org.embulk.config.ConfigDiff;
-import org.embulk.config.ConfigSource;
-import org.embulk.config.ConfigException;
-import org.embulk.config.TaskSource;
-import org.embulk.spi.Exec;
-import org.embulk.spi.FileInputPlugin;
-import org.embulk.spi.TransactionalFileInput;
 import org.embulk.util.file.InputStreamFileInput;
+import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
 public class CommandFileInputPlugin
-        implements FileInputPlugin
-{
+        implements FileInputPlugin {
     public interface PluginTask
-            extends Task
-    {
+            extends Task {
         @Config("command")
         public String getCommand();
 
@@ -41,18 +39,17 @@ public interface PluginTask
     }
 
     @Override
-    public ConfigDiff transaction(ConfigSource config, FileInputPlugin.Control control)
-    {
+    public ConfigDiff transaction(ConfigSource config, FileInputPlugin.Control control) {
         final ConfigMapper configMapper = CONFIG_MAPPER_FACTORY.createConfigMapper();
         final PluginTask task = configMapper.map(config, PluginTask.class);
 
         switch (task.getPipe()) {
-        case "stdout":
-            break;
-        case "stderr":
-            break;
-        default:
-            throw new ConfigException(String.format(
+            case "stdout":
+                break;
+            case "stderr":
+                break;
+            default:
+                throw new ConfigException(String.format(
                         "Unknown 'pipe' option '%s'. It must be either 'stdout' or 'stderr'", task.getPipe()));
         }
 
@@ -61,24 +58,21 @@ public ConfigDiff transaction(ConfigSource config, FileInputPlugin.Control contr
 
     @Override
     public ConfigDiff resume(TaskSource taskSource,
-            int taskCount,
-            FileInputPlugin.Control control)
-    {
+                             int taskCount,
+                             FileInputPlugin.Control control) {
         control.run(taskSource, taskCount);
 
         return CONFIG_MAPPER_FACTORY.newConfigDiff();
     }
 
     @Override
     public void cleanup(TaskSource taskSource,
-            int taskCount,
-            List<TaskReport> successTaskReports)
-    {
+                        int taskCount,
+                        List<TaskReport> successTaskReports) {
     }
 
     @Override
-    public TransactionalFileInput open(TaskSource taskSource, int taskIndex)
-    {
+    public TransactionalFileInput open(TaskSource taskSource, int taskIndex) {
         final TaskMapper taskMapper = CONFIG_MAPPER_FACTORY.createTaskMapper();
         final PluginTask task = taskMapper.map(taskSource, PluginTask.class);
 
@@ -90,12 +84,15 @@ public TransactionalFileInput open(TaskSource taskSource, int taskIndex)
 
         ProcessBuilder builder = new ProcessBuilder(cmdline.toArray(new String[cmdline.size()]));
         switch (task.getPipe()) {
-        case "stdout":
-            builder.redirectError(ProcessBuilder.Redirect.INHERIT);
-            break;
-        case "stderr":
-            builder.redirectOutput(ProcessBuilder.Redirect.INHERIT);
-            break;
+            case "stdout":
+                builder.redirectError(ProcessBuilder.Redirect.INHERIT);
+                break;
+            case "stderr":
+                builder.redirectOutput(ProcessBuilder.Redirect.INHERIT);
+                break;
+            default:
+                throw new IllegalStateException(String.format(
+                        "Unknown 'pipe' option '%s'. It must be either 'stdout' or 'stderr'", task.getPipe()));
         }
 
         try {
@@ -104,12 +101,15 @@ public TransactionalFileInput open(TaskSource taskSource, int taskIndex)
             InputStream stream = null;
             try {
                 switch (task.getPipe()) {
-                case "stdout":
-                    stream = process.getInputStream();
-                    break;
-                case "stderr":
-                    stream = process.getErrorStream();
-                    break;
+                    case "stdout":
+                        stream = process.getInputStream();
+                        break;
+                    case "stderr":
+                        stream = process.getErrorStream();
+                        break;
+                    default:
+                        throw new IllegalStateException(String.format(
+                                "Unknown 'pipe' option '%s'. It must be either 'stdout' or 'stderr'", task.getPipe()));
                 }
 
                 PluginFileInput input = new PluginFileInput(task, new ProcessWaitInputStream(stream, process));
@@ -126,30 +126,26 @@ public TransactionalFileInput open(TaskSource taskSource, int taskIndex)
         }
     }
 
-    static List<String> buildShell()
-    {
+    static List<String> buildShell() {
         String osName = System.getProperty("os.name");
-        if(osName.indexOf("Windows") >= 0) {
+        if (osName.indexOf("Windows") >= 0) {
             return Collections.unmodifiableList(Arrays.asList("PowerShell.exe", "-Command"));
         } else {
             return Collections.unmodifiableList(Arrays.asList("sh", "-c"));
         }
     }
 
     private static class ProcessWaitInputStream
-            extends FilterInputStream
-    {
+            extends FilterInputStream {
         private Process process;
 
-        public ProcessWaitInputStream(InputStream in, Process process)
-        {
+        public ProcessWaitInputStream(InputStream in, Process process) {
             super(in);
             this.process = process;
         }
 
         @Override
-        public int read() throws IOException
-        {
+        public int read() throws IOException {
             int c = super.read();
             if (c < 0) {
                 waitFor();
@@ -158,8 +154,7 @@ public int read() throws IOException
         }
 
         @Override
-        public int read(byte[] b) throws IOException
-        {
+        public int read(byte[] b) throws IOException {
             int c = super.read(b);
             if (c < 0) {
                 waitFor();
@@ -168,8 +163,7 @@ public int read(byte[] b) throws IOException
         }
 
         @Override
-        public int read(byte[] b, int off, int len) throws IOException
-        {
+        public int read(byte[] b, int off, int len) throws IOException {
             int c = super.read(b, off, len);
             if (c < 0) {
                 waitFor();
@@ -178,14 +172,12 @@ public int read(byte[] b, int off, int len) throws IOException
         }
 
         @Override
-        public void close() throws IOException
-        {
+        public void close() throws IOException {
             super.close();
             waitFor();
         }
 
-        private synchronized void waitFor() throws IOException
-        {
+        private synchronized void waitFor() throws IOException {
             if (process != null) {
                 int code;
                 try {
@@ -196,7 +188,7 @@ private synchronized void waitFor() throws IOException
                 process = null;
                 if (code != 0) {
                     throw new IOException(String.format(
-                                "Command finished with non-zero exit code. Exit code is %d.", code));
+                            "Command finished with non-zero exit code. Exit code is %d.", code));
                 }
             }
         }
@@ -205,22 +197,18 @@ private synchronized void waitFor() throws IOException
     // TODO almost copied from S3FileInputPlugin. include an InputStreamFileInput utility to embulk-core.
     public static class PluginFileInput
             extends InputStreamFileInput
-            implements TransactionalFileInput
-    {
+            implements TransactionalFileInput {
         private static class SingleFileProvider
-                implements InputStreamFileInput.Provider
-        {
+                implements InputStreamFileInput.Provider {
             private final InputStream stream;
             private boolean opened = false;
 
-            public SingleFileProvider(InputStream stream)
-            {
+            public SingleFileProvider(InputStream stream) {
                 this.stream = stream;
             }
 
             @Override
-            public InputStream openNext() throws IOException
-            {
+            public InputStream openNext() throws IOException {
                 if (opened) {
                     return null;
                 }
@@ -229,29 +217,29 @@ public InputStream openNext() throws IOException
             }
 
             @Override
-            public void close() throws IOException
-            {
+            public void close() throws IOException {
                 if (!opened) {
                     stream.close();
                 }
             }
         }
 
-        public PluginFileInput(PluginTask task, InputStream stream)
-        {
+        public PluginFileInput(PluginTask task, InputStream stream) {
             super(Exec.getBufferAllocator(), new SingleFileProvider(stream));
         }
 
-        public void abort() { }
+        public void abort() {
+        }
 
-        public TaskReport commit()
-        {
+        public TaskReport commit() {
             return CONFIG_MAPPER_FACTORY.newTaskReport();
         }
 
         @Override
-        public void close() { }
+        public void close() {
+        }
     }
+
     private static final Logger logger = LoggerFactory.getLogger(CommandFileInputPlugin.class);
 
     private static final ConfigMapperFactory CONFIG_MAPPER_FACTORY = ConfigMapperFactory.builder().addDefaultModules().build();

src/test/java/org/embulk/input/TestCommandFileInputPlugin.java

@@ -1,27 +1,23 @@
 package org.embulk.input;
 
+import static org.embulk.input.CommandFileInputPlugin.buildShell;
+import static org.junit.Assert.assertEquals;
+
 import java.util.Arrays;
 import java.util.Collections;
+import org.embulk.test.EmbulkTestRuntime;
 import org.junit.Rule;
 import org.junit.Test;
-import org.embulk.test.EmbulkTestRuntime;
-import static org.embulk.input.CommandFileInputPlugin.buildShell;
-
-import java.util.List;
 
-import static org.junit.Assert.assertEquals;
-
-public class TestCommandFileInputPlugin
-{
+public class TestCommandFileInputPlugin {
     @Rule
     public EmbulkTestRuntime runtime = new EmbulkTestRuntime();
 
     @Test
     public void testShell() {
         if (System.getProperty("os.name").indexOf("Windows") >= 0) {
             assertEquals(Collections.unmodifiableList(Arrays.asList("PowerShell.exe", "-Command")), buildShell());
-        }
-        else {
+        } else {
             assertEquals(Collections.unmodifiableList(Arrays.asList("sh", "-c")), buildShell());
         }
     }