Replace Guava functional helpers with streams

electrum · electrum · commit e449acfd628e · 2017-08-28T10:51:12.000-07:00
diff --git a/pom.xml b/pom.xml
@@ -63,6 +63,7 @@
         <dependency>
             <groupId>com.google.guava</groupId>
             <artifactId>guava</artifactId>
+            <version>21.0</version>
         </dependency>
 
         <!-- for testing -->
diff --git a/src/main/java/io/airlift/airline/Accessor.java b/src/main/java/io/airlift/airline/Accessor.java
@@ -1,7 +1,5 @@
 package io.airlift.airline;
 
-import com.google.common.base.Function;
-import com.google.common.base.Joiner;
 import com.google.common.collect.ImmutableList;
 import com.google.common.collect.Iterables;
 
@@ -19,6 +17,7 @@
 
 import static com.google.common.base.Preconditions.checkArgument;
 import static java.util.Objects.requireNonNull;
+import static java.util.stream.Collectors.joining;
 
 public class Accessor
 {
@@ -38,13 +37,8 @@ public Accessor(Iterable<Field> path)
         checkArgument(!Iterables.isEmpty(path), "path is empty");
 
         this.path = ImmutableList.copyOf(path);
-        this.name = this.path.get(0).getDeclaringClass().getSimpleName() + "." + Joiner.on('.').join(Iterables.transform(this.path, new Function<Field, String>()
-        {
-            public String apply(Field field)
-            {
-                return field.getName();
-            }
-        }));
+        this.name = this.path.get(0).getDeclaringClass().getSimpleName() + "." +
+                this.path.stream().map(Field::getName).collect(joining("."));
 
         Field field = this.path.get(this.path.size() - 1);
         multiValued = Collection.class.isAssignableFrom(field.getType());
diff --git a/src/main/java/io/airlift/airline/Cli.java b/src/main/java/io/airlift/airline/Cli.java
@@ -18,11 +18,9 @@
 
 package io.airlift.airline;
 
-import com.google.common.base.Function;
 import com.google.common.base.Preconditions;
 import com.google.common.collect.ImmutableList;
 import com.google.common.collect.ImmutableMap;
-import com.google.common.collect.Iterables;
 import io.airlift.airline.model.ArgumentsMetadata;
 import io.airlift.airline.model.CommandGroupMetadata;
 import io.airlift.airline.model.CommandMetadata;
@@ -36,8 +34,13 @@
 import java.util.Map;
 
 import static com.google.common.base.Preconditions.checkArgument;
+import static com.google.common.collect.ImmutableList.toImmutableList;
+import static com.google.common.collect.Streams.stream;
 import static io.airlift.airline.ParserUtil.createInstance;
 import static io.airlift.airline.ParserUtil.injectOptions;
+import static io.airlift.airline.model.MetadataLoader.loadCommand;
+import static io.airlift.airline.model.MetadataLoader.loadCommandGroup;
+import static io.airlift.airline.model.MetadataLoader.loadCommands;
 import static java.util.Objects.requireNonNull;
 
 public class Cli<C>
@@ -74,19 +77,18 @@ private Cli(String name,
 
         CommandMetadata defaultCommandMetadata = null;
         if (defaultCommand != null) {
-            defaultCommandMetadata = MetadataLoader.loadCommand(defaultCommand);
+            defaultCommandMetadata = loadCommand(defaultCommand);
         }
 
-        List<CommandMetadata> defaultCommandGroup = MetadataLoader.loadCommands(defaultGroupCommands);
+        List<CommandMetadata> defaultCommandGroup = loadCommands(defaultGroupCommands);
 
-        List<CommandGroupMetadata> commandGroups = ImmutableList.copyOf(Iterables.transform(groups, new Function<GroupBuilder<C>, CommandGroupMetadata>()
-        {
-            @Override
-            public CommandGroupMetadata apply(GroupBuilder<C> group)
-            {
-                return MetadataLoader.loadCommandGroup(group.name, group.description, MetadataLoader.loadCommand(group.defaultCommand), MetadataLoader.loadCommands(group.commands));
-            }
-        }));
+        List<CommandGroupMetadata> commandGroups = stream(groups)
+                .map(group -> loadCommandGroup(
+                        group.name,
+                        group.description,
+                        loadCommand(group.defaultCommand),
+                        loadCommands(group.commands)))
+                .collect(toImmutableList());
 
         this.metadata = MetadataLoader.loadGlobal(name, description, defaultCommandMetadata, defaultCommandGroup, commandGroups);
     }
diff --git a/src/main/java/io/airlift/airline/CommandSuggester.java b/src/main/java/io/airlift/airline/CommandSuggester.java
@@ -19,7 +19,7 @@ public class CommandSuggester
     public Iterable<String> suggest()
     {
         ImmutableList.Builder<String> suggestions = ImmutableList.<String>builder()
-                .addAll(concat(transform(command.getCommandOptions(), OptionMetadata.optionsGetter())));
+                .addAll(concat(transform(command.getCommandOptions(), OptionMetadata::getOptions)));
 
         if (command.getArguments() != null) {
             suggestions.add("--");
diff --git a/src/main/java/io/airlift/airline/GlobalSuggester.java b/src/main/java/io/airlift/airline/GlobalSuggester.java
@@ -20,9 +20,9 @@ public class GlobalSuggester
     public Iterable<String> suggest()
     {
         return concat(
-                transform(metadata.getCommandGroups(), CommandGroupMetadata.nameGetter()),
-                transform(metadata.getDefaultGroupCommands(), CommandMetadata.nameGetter()),
-                concat(transform(metadata.getOptions(), OptionMetadata.optionsGetter()))
+                transform(metadata.getCommandGroups(), CommandGroupMetadata::getName),
+                transform(metadata.getDefaultGroupCommands(), CommandMetadata::getName),
+                concat(transform(metadata.getOptions(), OptionMetadata::getOptions))
         );
     }
 }
diff --git a/src/main/java/io/airlift/airline/GlobalUsageSummary.java b/src/main/java/io/airlift/airline/GlobalUsageSummary.java
@@ -1,21 +1,17 @@
 package io.airlift.airline;
 
-import com.google.common.base.Function;
-import com.google.common.collect.Collections2;
 import com.google.common.collect.ImmutableList;
 import io.airlift.airline.model.CommandGroupMetadata;
 import io.airlift.airline.model.CommandMetadata;
 import io.airlift.airline.model.GlobalMetadata;
-import io.airlift.airline.model.OptionMetadata;
 
-import java.util.ArrayList;
 import java.util.List;
 import java.util.Map;
 import java.util.TreeMap;
 
 import static com.google.common.base.MoreObjects.firstNonNull;
 import static com.google.common.base.Preconditions.checkArgument;
-import static io.airlift.airline.UsageHelper.toUsage;
+import static com.google.common.collect.ImmutableList.toImmutableList;
 import static java.util.stream.Collectors.toList;
 
 public class GlobalUsageSummary
@@ -58,17 +54,11 @@ public void usage(GlobalMetadata global, UsagePrinter out)
         //
 
         // build arguments
-        List<String> commandArguments = new ArrayList<>();
-        commandArguments.addAll(Collections2.transform(global.getOptions(), new Function<OptionMetadata, String>()
-        {
-            public String apply(OptionMetadata option)
-            {
-                if (option.isHidden()) {
-                    return null;
-                }
-                return toUsage(option);
-            }
-        }));
+        List<String> commandArguments = global.getOptions().stream()
+                .filter(option -> !option.isHidden())
+                .map(UsageHelper::toUsage)
+                .collect(toImmutableList());
+
         out.newPrinterWithHangingIndent(8)
                 .append("usage:")
                 .append(global.getName())
diff --git a/src/main/java/io/airlift/airline/GroupSuggester.java b/src/main/java/io/airlift/airline/GroupSuggester.java
@@ -19,8 +19,8 @@ public class GroupSuggester
     public Iterable<String> suggest()
     {
         return concat(
-                transform(group.getCommands(), CommandMetadata.nameGetter()),
-                concat(transform(group.getOptions(), OptionMetadata.optionsGetter()))
+                transform(group.getCommands(), CommandMetadata::getName),
+                concat(transform(group.getOptions(), OptionMetadata::getOptions))
         );
     }
 }
diff --git a/src/main/java/io/airlift/airline/Parser.java b/src/main/java/io/airlift/airline/Parser.java
@@ -38,7 +38,7 @@ public ParseState parse(GlobalMetadata metadata, Iterable<String> params)
 
         // parse group
         if (tokens.hasNext()) {
-            CommandGroupMetadata group = find(metadata.getCommandGroups(), compose(equalTo(tokens.peek()), CommandGroupMetadata.nameGetter()), null);
+            CommandGroupMetadata group = find(metadata.getCommandGroups(), compose(equalTo(tokens.peek()), CommandGroupMetadata::getName), null);
             if (group != null) {
                 tokens.next();
                 state = state.withGroup(group).pushContext(Context.GROUP);
@@ -54,7 +54,7 @@ public ParseState parse(GlobalMetadata metadata, Iterable<String> params)
         }
 
         if (tokens.hasNext()) {
-            CommandMetadata command = find(expectedCommands, compose(equalTo(tokens.peek()), CommandMetadata.nameGetter()), null);
+            CommandMetadata command = find(expectedCommands, compose(equalTo(tokens.peek()), CommandMetadata::getName), null);
             if (command == null) {
                 while (tokens.hasNext()) {
                     state = state.withUnparsedInput(tokens.next());
diff --git a/src/main/java/io/airlift/airline/UsageHelper.java b/src/main/java/io/airlift/airline/UsageHelper.java
@@ -1,23 +1,16 @@
 package io.airlift.airline;
 
-import com.google.common.base.Function;
-import com.google.common.base.Joiner;
 import com.google.common.collect.ComparisonChain;
-import com.google.common.collect.ImmutableList;
-import com.google.common.collect.Lists;
 import io.airlift.airline.model.ArgumentsMetadata;
 import io.airlift.airline.model.CommandMetadata;
 import io.airlift.airline.model.OptionMetadata;
 
-import javax.annotation.Nullable;
-
 import java.util.Comparator;
 import java.util.List;
 import java.util.Set;
 
-import static com.google.common.collect.Iterables.filter;
-import static com.google.common.collect.Iterables.transform;
-import static io.airlift.airline.model.OptionMetadata.isHiddenPredicate;
+import static com.google.common.collect.ImmutableList.toImmutableList;
+import static java.util.stream.Collectors.joining;
 
 public class UsageHelper
 {
@@ -54,35 +47,21 @@ public int compare(CommandMetadata o1, CommandMetadata o2)
 
     public static String toDescription(OptionMetadata option)
     {
-        Set<String> options = option.getOptions();
-        StringBuilder stringBuilder = new StringBuilder();
-
-        final String argumentString;
-        if (option.getArity() > 0) {
-            argumentString = Joiner.on(" ").join(Lists.transform(ImmutableList.of(option.getTitle()), new Function<String, String>()
-            {
-                public String apply(@Nullable String argument)
-                {
-                    return "<" + argument + ">";
-                }
-            }));
-        }
-        else {
-            argumentString = null;
-        }
-
-        Joiner.on(", ").appendTo(stringBuilder, transform(options, new Function<String, String>()
-        {
-            public String apply(@Nullable String option)
-            {
-                if (argumentString != null) {
-                    return option + " " + argumentString;
-                }
-                return option;
-            }
-        }));
+        return optionString(option, ", ");
+    }
 
-        return stringBuilder.toString();
+    private static String optionString(OptionMetadata option, String delimiter)
+    {
+        String argument = (option.getArity() > 0) ? ("<" + option.getTitle() + ">") : null;
+
+        return option.getOptions().stream()
+                .map(value -> {
+                    if (argument != null) {
+                        return value + " " + argument;
+                    }
+                    return value;
+                })
+                .collect(joining(delimiter));
     }
 
     public static String toDescription(ArgumentsMetadata arguments)
@@ -107,32 +86,7 @@ public static String toUsage(OptionMetadata option)
             stringBuilder.append('(');
         }
 
-        final String argumentString;
-        if (option.getArity() > 0) {
-            argumentString = Joiner.on(" ").join(transform(ImmutableList.of(option.getTitle()), new Function<String, String>()
-            {
-                public String apply(@Nullable String argument)
-                {
-                    return "<" + argument + ">";
-                }
-            }));
-        }
-        else {
-            argumentString = null;
-        }
-
-        Joiner.on(" | ").appendTo(stringBuilder, transform(options, new Function<String, String>()
-        {
-            public String apply(@Nullable String option)
-            {
-                if (argumentString != null) {
-                    return option + " " + argumentString;
-                }
-                else {
-                    return option;
-                }
-            }
-        }));
+        stringBuilder.append(optionString(option, " | "));
 
         if (options.size() > 1) {
             stringBuilder.append(')');
@@ -174,12 +128,9 @@ public static String toUsage(ArgumentsMetadata arguments)
 
     public static List<String> toSynopsisUsage(List<OptionMetadata> options)
     {
-        return ImmutableList.copyOf(transform(filter(options, isHiddenPredicate()), new Function<OptionMetadata, String>()
-        {
-            public String apply(OptionMetadata option)
-            {
-                return toUsage(option);
-            }
-        }));
+        return options.stream()
+                .filter(input -> !input.isHidden())
+                .map(UsageHelper::toUsage)
+                .collect(toImmutableList());
     }
 }
diff --git a/src/main/java/io/airlift/airline/model/CommandGroupMetadata.java b/src/main/java/io/airlift/airline/model/CommandGroupMetadata.java
@@ -1,6 +1,5 @@
 package io.airlift.airline.model;
 
-import com.google.common.base.Function;
 import com.google.common.collect.ImmutableList;
 
 import java.util.List;
@@ -60,15 +59,4 @@ public String toString()
         sb.append('}');
         return sb.toString();
     }
-
-    public static Function<CommandGroupMetadata, String> nameGetter()
-    {
-        return new Function<CommandGroupMetadata, String>()
-        {
-            public String apply(CommandGroupMetadata input)
-            {
-                return input.getName();
-            }
-        };
-    }
 }
diff --git a/src/main/java/io/airlift/airline/model/CommandMetadata.java b/src/main/java/io/airlift/airline/model/CommandMetadata.java
@@ -1,6 +1,5 @@
 package io.airlift.airline.model;
 
-import com.google.common.base.Function;
 import com.google.common.collect.ImmutableList;
 import io.airlift.airline.Accessor;
 
@@ -104,15 +103,4 @@ public String toString()
         sb.append('}');
         return sb.toString();
     }
-
-    public static Function<CommandMetadata, String> nameGetter()
-    {
-        return new Function<CommandMetadata, String>()
-        {
-            public String apply(CommandMetadata input)
-            {
-                return input.getName();
-            }
-        };
-    }
 }
diff --git a/src/main/java/io/airlift/airline/model/MetadataLoader.java b/src/main/java/io/airlift/airline/model/MetadataLoader.java
diff --git a/src/main/java/io/airlift/airline/model/OptionMetadata.java b/src/main/java/io/airlift/airline/model/OptionMetadata.java
diff --git a/src/test/java/io/airlift/airline/TestCommand.java b/src/test/java/io/airlift/airline/TestCommand.java
diff --git a/src/test/java/io/airlift/airline/TestSingleCommand.java b/src/test/java/io/airlift/airline/TestSingleCommand.java

Original file line number	Diff line number	Diff line change
`@@ -19,7 +19,7 @@ public class CommandSuggester`
`19`	`19`	`public Iterable<String> suggest()`
`20`	`20`	`{`
`21`	`21`	`ImmutableList.Builder<String> suggestions = ImmutableList.<String>builder()`
`22`		`- .addAll(concat(transform(command.getCommandOptions(), OptionMetadata.optionsGetter())));`
	`22`	`+ .addAll(concat(transform(command.getCommandOptions(), OptionMetadata::getOptions)));`
`23`	`23`
`24`	`24`	`if (command.getArguments() != null) {`
`25`	`25`	`suggestions.add("--");`
Original file line number	Diff line number	Diff line change
`@@ -20,9 +20,9 @@ public class GlobalSuggester`
`20`	`20`	`public Iterable<String> suggest()`
`21`	`21`	`{`
`22`	`22`	`return concat(`
`23`		`- transform(metadata.getCommandGroups(), CommandGroupMetadata.nameGetter()),`
`24`		`- transform(metadata.getDefaultGroupCommands(), CommandMetadata.nameGetter()),`
`25`		`- concat(transform(metadata.getOptions(), OptionMetadata.optionsGetter()))`
	`23`	`+ transform(metadata.getCommandGroups(), CommandGroupMetadata::getName),`
	`24`	`+ transform(metadata.getDefaultGroupCommands(), CommandMetadata::getName),`
	`25`	`+ concat(transform(metadata.getOptions(), OptionMetadata::getOptions))`
`26`	`26`	`);`
`27`	`27`	`}`
`28`	`28`	`}`
Original file line number	Diff line number	Diff line change
`@@ -19,8 +19,8 @@ public class GroupSuggester`
`19`	`19`	`public Iterable<String> suggest()`
`20`	`20`	`{`
`21`	`21`	`return concat(`
`22`		`- transform(group.getCommands(), CommandMetadata.nameGetter()),`
`23`		`- concat(transform(group.getOptions(), OptionMetadata.optionsGetter()))`
	`22`	`+ transform(group.getCommands(), CommandMetadata::getName),`
	`23`	`+ concat(transform(group.getOptions(), OptionMetadata::getOptions))`
`24`	`24`	`);`
`25`	`25`	`}`
`26`	`26`	`}`