Can use alternative parameters instead of required parameters

Author: luontola

README.md

@@ -96,16 +96,7 @@ Copyright (c) 2013-2015  Esko Luontola <www.orfjackal.net>
 This software is released under the Apache License 2.0.
 The license text is at http://www.apache.org/licenses/LICENSE-2.0
 
-Required system properties:
-
-  retrolambda.inputDir
-      Input directory from where the original class files are read.
-
-  retrolambda.classpath
-      Classpath containing the original class files and their dependencies.
-      Uses ; or : as the path separator, see java.io.File#pathSeparatorChar
-
-Optional system properties:
+Configurable system properties:
 
   retrolambda.bytecodeVersion
       Major version number for the generated bytecode. For a list, see
@@ -119,11 +110,18 @@ Optional system properties:
       with one execution of Retrolambda.
       Disabled by default. Enable by setting to "true"
 
+  retrolambda.inputDir (required)
+      Input directory from where the original class files are read.
+
   retrolambda.outputDir
       Output directory into where the generated class files are written.
       Defaults to same as retrolambda.inputDir
 
-  retrolambda.classpathFile
+  retrolambda.classpath (required)
+      Classpath containing the original class files and their dependencies.
+      Uses ; or : as the path separator, see java.io.File#pathSeparatorChar
+
+  retrolambda.classpathFile (alternative)
       File listing the classpath entries.
       Alternative to retrolambda.classpath for avoiding the command line
       length limit. The file must list one file per line with UTF-8 encoding.
@@ -133,7 +131,7 @@ Optional system properties:
       This is useful for a build tool to support incremental compilation.
       Uses ; or : as the path separator, see java.io.File#pathSeparatorChar
 
-  retrolambda.includedFilesFile
+  retrolambda.includedFilesFile (alternative)
       File listing the files to process, instead of processing all files.
       Alternative to retrolambda.includedFiles for avoiding the command line
       length limit. The file must list one file per line with UTF-8 encoding.

retrolambda/src/main/java/net/orfjackal/retrolambda/Config.java

@@ -24,8 +24,8 @@ public class Config {
     public static final String INCLUDED_FILES_FILE = INCLUDED_FILES + "File";
 
     private static final List<String> requiredProperties = new ArrayList<>();
-    private static final List<String> requiredPropertiesHelp = new ArrayList<>();
-    private static final List<String> optionalPropertiesHelp = new ArrayList<>();
+    private static final Map<String, String> alternativeProperties = new HashMap<>();
+    private static final List<String> propertiesHelp = new ArrayList<>();
     private static final Map<Integer, String> bytecodeVersionNames = new HashMap<>();
 
     static {
@@ -51,13 +51,26 @@ public boolean isFullyConfigured() {
 
     private boolean hasAllRequiredProperties() {
         for (String requiredParameter : requiredProperties) {
-            if (p.getProperty(requiredParameter) == null) {
+            if (!isConfigured(requiredParameter)) {
                 return false;
             }
         }
         return true;
     }
 
+    private boolean isConfigured(String parameter) {
+        if (p.getProperty(parameter) != null) {
+            return true;
+        }
+        for (Map.Entry<String, String> alt : alternativeProperties.entrySet()) {
+            if (alt.getValue().equals(parameter) &&
+                    p.getProperty(alt.getKey()) != null) {
+                return true;
+            }
+        }
+        return false;
+    }
+
 
     // bytecode version
 
@@ -133,7 +146,7 @@ public Path getOutputDir() {
         requiredParameterHelp(CLASSPATH,
                 "Classpath containing the original class files and their dependencies.",
                 "Uses ; or : as the path separator, see java.io.File#pathSeparatorChar");
-        optionalParameterHelp(CLASSPATH_FILE,
+        alternativeParameterHelp(CLASSPATH_FILE, CLASSPATH,
                 "File listing the classpath entries.",
                 "Alternative to " + CLASSPATH + " for avoiding the command line",
                 "length limit. The file must list one file per line with UTF-8 encoding.");
@@ -177,7 +190,7 @@ private static List<Path> readPathList(Path file) {
                 "List of files to process, instead of processing all files.",
                 "This is useful for a build tool to support incremental compilation.",
                 "Uses ; or : as the path separator, see java.io.File#pathSeparatorChar");
-        optionalParameterHelp(INCLUDED_FILES_FILE,
+        alternativeParameterHelp(INCLUDED_FILES_FILE, INCLUDED_FILES,
                 "File listing the files to process, instead of processing all files.",
                 "Alternative to " + INCLUDED_FILES + " for avoiding the command line",
                 "length limit. The file must list one file per line with UTF-8 encoding.");
@@ -213,13 +226,9 @@ public String getHelp() {
                 "This software is released under the Apache License 2.0.\n" +
                 "The license text is at http://www.apache.org/licenses/LICENSE-2.0\n" +
                 "\n" +
-                "Required system properties:\n" +
+                "Configurable system properties:\n" +
                 "\n" +
-                requiredPropertiesHelp.stream().reduce((a, b) -> a + "\n" + b).get() +
-                "\n" +
-                "Optional system properties:\n" +
-                "\n" +
-                optionalPropertiesHelp.stream().reduce((a, b) -> a + "\n" + b).get() +
+                propertiesHelp.stream().reduce((a, b) -> a + "\n" + b).get() +
                 "\n" +
                 "If the Java agent is used, then Retrolambda will use it to capture the\n" +
                 "lambda classes generated by Java. Otherwise Retrolambda will hook into\n" +
@@ -229,18 +238,24 @@ public String getHelp() {
 
     private static void requiredParameterHelp(String key, String... lines) {
         requiredProperties.add(key);
-        requiredPropertiesHelp.add(formatPropertyHelp(key, lines));
+        propertiesHelp.add(formatPropertyHelp(key, "required", lines));
+    }
+
+    private static void alternativeParameterHelp(String key, String replaces, String... lines) {
+        alternativeProperties.put(key, replaces);
+        propertiesHelp.add(formatPropertyHelp(key, "alternative", lines));
     }
 
     private static void optionalParameterHelp(String key, String... lines) {
-        optionalPropertiesHelp.add(formatPropertyHelp(key, lines));
+        propertiesHelp.add(formatPropertyHelp(key, "", lines));
     }
 
-    private static String formatPropertyHelp(String key, String... lines) {
-        String s = "  " + key + "\n";
+    private static String formatPropertyHelp(String key, String tag, String... lines) {
+        tag = tag.isEmpty() ? "" : " (" + tag + ")";
+        String help = "  " + key + tag + "\n";
         for (String line : lines) {
-            s += "      " + line + "\n";
+            help += "      " + line + "\n";
         }
-        return s;
+        return help;
     }
 }

retrolambda/src/test/java/net/orfjackal/retrolambda/ConfigTest.java

@@ -28,6 +28,24 @@ private Config config() {
         return new Config(systemProperties);
     }
 
+    @Test
+    public void is_fully_configured_when_required_properties_are_set() {
+        assertThat("before", config().isFullyConfigured(), is(false));
+
+        systemProperties.setProperty(Config.INPUT_DIR, "");
+        systemProperties.setProperty(Config.CLASSPATH, "");
+
+        assertThat("after", config().isFullyConfigured(), is(true));
+    }
+
+    @Test
+    public void can_use_alternative_parameter_instead_of_required_parameter() {
+        systemProperties.setProperty(Config.INPUT_DIR, "");
+        systemProperties.setProperty(Config.CLASSPATH_FILE, "");
+
+        assertThat("is fully configured?", config().isFullyConfigured(), is(true));
+    }
+
     @Test
     public void bytecode_version() {
         assertThat("defaults to Java 7", config().getBytecodeVersion(), is(51));