Added support for "public static void main" method to become script

Troy Melhase · Troy Melhase · commit 251f6ba5f1aa · 2007-02-14T23:00:28.000Z
call. Closes natural#4. Also added tests directory and HelloWorldApp.java sample.
diff --git a/java2python/lib/defaultconfig.py b/java2python/lib/defaultconfig.py
@@ -33,6 +33,11 @@
 ## if True, a default docstring is generated for method statements.
 writeMethodDocString = False
 
+## if True, and if input source contains a "public static void main"
+## method, a block is written to the end of the file to call the class
+## method with sys.argv.
+writeMainMethodScript = True
+
 ## if True, classes without base classes will instead inherit from
 ## object.
 classesInheritObject = True
@@ -119,5 +124,6 @@
 ## corresponding statements from this mapping.  this value can be
 ## replaced and/or augmented via user-defined configuration modules.
 modifierDecoratorMap = {
-    'synchronized':'## original method synchronized'
+    'synchronized':'## original method synchronized',
+    'static':'@classmethod',
 }
diff --git a/java2python/lib/sourcetypes.py b/java2python/lib/sourcetypes.py
@@ -390,9 +390,11 @@ def writeTo(self, output, indent):
         output.write('\n')
         Source.writeTo(self, output, indent)
         self.writeExtraLines('moduleEpilogue', output)
-        
+        if self.config.last('writeMainMethodScript'):
+            self.writeMainBlock(output)
+            
     def writeExtraLines(self, name, output):
-        """ writes an sequence of lines given a config attribute name
+        """ writes a sequence of lines given a config attribute name
 
         Lines may be callable.  Refer to the defaultconfig module for
         details.
@@ -409,7 +411,29 @@ def writeExtraLines(self, name, output):
                     pass
                 output.write('%s\n' % (line, ))
 
+    def writeMainBlock(self, output):
+        """ writes a block to call the module as a script
 
+        @param output writable file-like object
+        @return None
+        """
+        try:
+            cls = [c for c in self.lines if getattr(c, 'isClass', None)][0]
+            methods = [m for m in cls.lines if getattr(m, 'isMethod', None)]
+            main = [m for m in methods if m.name == 'main'][0]
+        except (Exception, ):
+            pass
+        else:
+            mods = main.modifiers
+            typ = main.type
+            if ('public' in mods) and ('static' in mods) and (typ == 'void'):
+                name = cls.name
+                offset = self.I(1)
+                output.write("if __name__ == '__main__':\n")
+                output.write("%simport sys\n" % offset)
+                output.write("%s%s.main(sys.argv)\n" % (offset, name))
+
+    
 class Class(Source):
     """ Class -> specialized block type
 
@@ -550,9 +574,12 @@ class Method(Source):
     """ Method -> specialized block type
 
     """
+    instanceFirstParam = ('object', 'self')
+    classFirstParam = ('type', 'cls')
+    
     def __init__(self, parent, name):
         Source.__init__(self, parent=parent, name=name)
-        self.parameters = [('object', 'self'), ]
+        self.parameters = [self.instanceFirstParam, ]
 
     def addModifier(self, name):
         """ adds named modifier to method
@@ -570,6 +597,9 @@ def addModifier(self, name):
         else:
             if deco not in self.preamble:
                 self.preamble.append(deco)
+                if (deco == '@classmethod') and (self.parameters) \
+                       and (self.parameters[0] == self.instanceFirstParam):
+                    self.parameters[0] = self.classFirstParam
         Source.addModifier(self, name)
         
     def addParameter(self, typ, name):
diff --git a/java2python/lib/walker.g b/java2python/lib/walker.g
@@ -102,11 +102,12 @@ returns [typ]
 
 
 modifiers [block, mod=None]
-    :   #(MODIFIERS (mod = modifier[block])*)
+    :   #(MODIFIERS (mod = modifier[block]
         {
         if mod:
             block.addModifier(mod)
-        }
+        })*
+        )
     ;
 
 
@@ -214,6 +215,9 @@ method_def [block]
             method_head[meth]
             (statement_list[meth])?
         )
+        {
+        meth.type = typ
+        }
     ;
 
 
diff --git a/java2python/tests/HelloWorldApp.java b/java2python/tests/HelloWorldApp.java
@@ -0,0 +1,9 @@
+class HelloWorldApp {
+    public void foo() {
+        System.out.println("FOO");
+    }
+    public static void main(String[] args) {
+        System.out.println("Hello, world.");
+        System.out.println(args);
+    }
+}

Original file line number	Diff line number	Diff line change
`@@ -102,11 +102,12 @@ returns [typ]`
`102`	`102`
`103`	`103`
`104`	`104`	`modifiers [block, mod=None]`
`105`		`- : #(MODIFIERS (mod = modifier[block])*)`
	`105`	`+ : #(MODIFIERS (mod = modifier[block]`
`106`	`106`	`{`
`107`	`107`	`if mod:`
`108`	`108`	`block.addModifier(mod)`
`109`		`- }`
	`109`	`+ })*`
	`110`	`+ )`
`110`	`111`	`;`
`111`	`112`
`112`	`113`
`@@ -214,6 +215,9 @@ method_def [block]`
`214`	`215`	`method_head[meth]`
`215`	`216`	`(statement_list[meth])?`
`216`	`217`	`)`
	`218`	`+ {`
	`219`	`+ meth.type = typ`
	`220`	`+ }`
`217`	`221`	`;`
`218`	`222`
`219`	`223`