Add API to get a specific method given the qualified class name and the method signature.

Signed-off-by: Rahul Krishna <[email protected]>

Author: rahlk

src/analysis/java/JavaAnalysis.ts

@@ -19,7 +19,7 @@ import fg from "fast-glob";
 import fs from "fs";
 import log from "loglevel";
 import { spawnSync } from "node:child_process";
-import { JApplication } from "../../models/java";
+import { JApplication, JCompilationUnit } from "../../models/java";
 import * as types from "../../models/java/types";
 import { JType } from "../../models/java";
 import os from "os";
@@ -152,6 +152,15 @@ export class JavaAnalysis {
     return this.application;
   }
 
+  /**
+   * Get the symbol table from the application.
+   * @returns {Promise<Record<string, types.JCompilationUnitType>>} A promise that resolves to a record of file paths and their
+   * corresponding {@link JCompilationUnitType} objects
+   * 
+   * @notes This method retrieves the symbol table from the application, which contains information about all
+   * compilation units in the Java application. The returned record contains file paths as keys and their
+   * corresponding {@link JCompilationUnit} objects as values.
+   */
   public async getSymbolTable(): Promise<Record<string, types.JCompilationUnitType>> {
     return (await this.getApplication()).symbol_table;
   }
@@ -222,4 +231,21 @@ export class JavaAnalysis {
     const classForWhichMethodsAreRequested = await this.getClassByQualifiedName(qualifiedName);
     return classForWhichMethodsAreRequested ? Object.values(classForWhichMethodsAreRequested.callable_declarations ?? {}) : [];
   }
+
+  /**
+   * Get a specific methods within a specific class by its qualified name.
+   * @param {string} qualifiedName - The qualified name of the class to retrieve
+   * @param {string} methodName - The name of the method to retrieve
+   * @returns {Promise<types.JCallableType>} A promise that resolves to the {@link JCallable} object representing the method.
+   * @throws {Error} If the class or method is not found in the application.
+   * 
+   * @notes This method retrieves a specific method from the application by its qualified name and method name.
+   * If the method is found, it returns the corresponding {@link JCallableType} object. If the method is not found,
+   * it throws an error.
+   */
+  public async getMethodByQualifiedName(qualifiedName: string, methodName: string): Promise<types.JCallableType> {
+    return (await this.getAllMethodsByClass(qualifiedName)).find(
+      (method) => method.signature === methodName
+    ) ?? (() => { throw new Error(`Method ${methodName} not found in class ${qualifiedName}.`); })();
+  }
 }

test/unit/analysis/java/JavaAnalysis.test.ts

@@ -1,4 +1,4 @@
-import { JType } from "../../../../src/models/java/";
+import { JCallable, JType } from "../../../../src/models/java/";
 import { daytraderJavaAnalysis } from "../../../conftest";
 import { expect, test } from "bun:test";
 
@@ -46,4 +46,11 @@ test("Must get all methods in a specific class in the application", async () =>
     (
       await daytraderJavaAnalysis.getAllMethodsByClass("com.ibm.websphere.samples.daytrader.impl.direct.TradeDirect")).length
   ).toBeGreaterThan(0)
+});
+
+test("Must get a specific method in a specific class in the application", async () => {
+  const method = await daytraderJavaAnalysis.getMethodByQualifiedName(
+    "com.ibm.websphere.samples.daytrader.impl.direct.TradeDirect", "publishQuotePriceChange(QuoteDataBean, BigDecimal, BigDecimal, double)");
+
+  expect(async () => JCallable.parse(method)).not.toThrow();
 });