From 8a37418ebb03583e8b64343a7a1c3171218616ce Mon Sep 17 00:00:00 2001
From: Claudio Maggioni <maggicl@usi.ch>
Date: Tue, 14 Feb 2023 11:01:31 +0100
Subject: [PATCH] god-2022: part 1 done

---
 proj2022/.gitignore          |  2 ++
 proj2022/README.md           | 15 +++++++++
 proj2022/find_god_classes.py | 63 ++++++++++++++++++++++++++++++++++++
 proj2022/requirements.txt    |  2 ++
 4 files changed, 82 insertions(+)
 create mode 100644 proj2022/.gitignore
 create mode 100644 proj2022/README.md
 create mode 100755 proj2022/find_god_classes.py
 create mode 100644 proj2022/requirements.txt

diff --git a/proj2022/.gitignore b/proj2022/.gitignore
new file mode 100644
index 0000000..84a2d97
--- /dev/null
+++ b/proj2022/.gitignore
@@ -0,0 +1,2 @@
+xerces2/
+env/
diff --git a/proj2022/README.md b/proj2022/README.md
new file mode 100644
index 0000000..e53135e
--- /dev/null
+++ b/proj2022/README.md
@@ -0,0 +1,15 @@
+# IMA - God classes project
+
+## Xerces2
+
+Downloaded from: https://dlcdn.apache.org//xerces/j/source/Xerces-J-src.2.12.2.zip
+
+## Install dependencies
+
+```shell
+# create venv
+python -m venv env
+source env/bin/activate
+
+pip3 install -r requirements.txt
+```
diff --git a/proj2022/find_god_classes.py b/proj2022/find_god_classes.py
new file mode 100755
index 0000000..e88d16a
--- /dev/null
+++ b/proj2022/find_god_classes.py
@@ -0,0 +1,63 @@
+#!/usr/bin/env python3
+import javalang
+import os
+import pandas as pd
+
+DIR: str = os.path.dirname(os.path.realpath(__file__))
+SOURCES: str = DIR + '/xerces2/src'
+
+# God class if:
+# |M(C)| > E(M) + 6 V(M)
+# (number of methods greater than average across all classes plus 6 times the
+# standard deviation)
+
+def parse(path: str) -> list[tuple[str, str]]:
+    # Get the AST of the file
+    with open(path) as file:
+        data = file.read()
+    tree = javalang.parse.parse(data)
+    
+    # Fetch package name from package declaration
+    # if node is missing, assuming default package ('')
+    package_name = ''
+    for _, node in tree.filter(javalang.tree.PackageDeclaration):
+        package_name = node.name
+        break
+
+    # Get all classes and number of methods for each one
+    rows: list[tuple[str, str]] = []
+    for _, node in tree.filter(javalang.tree.ClassDeclaration):
+        fqdn = package_name + '.' + node.name
+        rows.append((fqdn, len(node.methods),))
+    
+    return rows
+
+
+def create_df(root) -> pd.DataFrame:
+    frame = pd.DataFrame(columns=['class_name', 'method_num'])
+
+    i: int = 0
+    for path, dirs, files in os.walk(root):
+        for f in files:
+            if f.endswith('.java'):
+                # for each java file, add all entries found to dataframe
+                for row in parse(path + '/' + f):
+                    frame.loc[i] = row
+                    i += 1
+    
+    return frame
+
+
+def main():
+    df = create_df(SOURCES)
+
+    mean = df.loc[:, 'method_num'].mean()
+    std = df.loc[:, 'method_num'].std()
+    treshold = mean + 6 * std
+
+    god_classes_df = df[df['method_num'] > treshold]
+    print(god_classes_df)
+
+
+if __name__ == '__main__':
+    main()
\ No newline at end of file
diff --git a/proj2022/requirements.txt b/proj2022/requirements.txt
new file mode 100644
index 0000000..bad8ae3
--- /dev/null
+++ b/proj2022/requirements.txt
@@ -0,0 +1,2 @@
+javalang==0.13.0
+pandas==1.5.2