Performance: O(1) Listener add/delete

[morris821028]

This is a simple test case for performance turning.

The origin type Vector will use O(n) time on removeElement.

package bsh;

import java.util.Scanner;

public class PerformanceStateTest {
	public static String getName(String s) {
		return s + "A";
	}
	
	public static void main(String[] args) {
		final Interpreter interpreter = new Interpreter();

		Runtime runtime = Runtime.getRuntime();

		long usedMemoryBefore = 0;
		long usedMemoryAfter = 0;
		long start;
		long end;
		
		Scanner cin = new Scanner(System.in);
//		
		cin.next();
		
		try {
			interpreter.eval("import bsh.PerformanceStateTest;");
			interpreter.eval("a = \"1\" + \"2\";");
			interpreter.eval("String getName(String s) { return \"\" + PerformanceStateTest.getName(s); }");
			interpreter.eval("String getName2(String s) { if (s.charAt(0) == '1') return s + \"B\"; }");
			interpreter.eval("b = \"3\" + \"4\";");
		} catch (EvalError e) {
			e.printStackTrace();
		}
		
		start = System.currentTimeMillis();
		try {
			String v = null;
			for (int i = 0; i < 500000; i++) {
				v = (String) interpreter.eval("getName(\"123\")");
			}
			System.out.println(v);
		} catch (EvalError e) {
			e.printStackTrace();
		}
		end = System.currentTimeMillis();
		final long goldTime = end - start;
		System.out.printf("time %d", goldTime);
	}
}

[codecov]

Codecov Report

Merging #562 into master will decrease coverage by <.01%.
The diff coverage is 100%.

@@             Coverage Diff              @@
##             master     #562      +/-   ##
============================================
- Coverage     71.06%   71.05%   -0.01%     
  Complexity     2723     2723              
============================================
  Files           106      106              
  Lines          8912     8911       -1     
  Branches       1745     1745              
============================================
- Hits           6333     6332       -1     
  Misses         2174     2174              
  Partials        405      405

Impacted Files	Coverage Δ	Complexity Δ
src/main/java/bsh/classpath/ClassManagerImpl.java	64.67% <100%> (-0.22%)	39 <8> (ø)

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[nickl-]

@morris821028 Nice 1 Thanx