FindOverridableMethodCall.visitBootstrapMethods(BootstrapMethods) contains invisible \u200b character

[iloveeclipse]

I'm unable to compile current spotbugs code in Eclipse because of FindOverridableMethodCall.visitBootstrapMethods(BootstrapMethods) method.

The method ends with \u200b unicode character and Eclipse compiler assumes that this method can't override the visitBootstrapMethods defined in the org.apache.bcel.classfile.Visitor.visitBootstrapMethods(BootstrapMethods).

The method was added in #1716.

I will push a patch to remove the invisible character and will investigate which compiler is right.
I see that Eclipse 4.12 - 4.22 accepts \u200b in source file and preserves as part of the method name in the class file.
However, javac 1.8 - 17 accepts \u200b in the source file but does not preserve it as part of the method name in the class file.

Reported bug against ecj compiler: https://bugs.eclipse.org/bugs/show_bug.cgi?id=578063

[iloveeclipse]

Patch that shows the difference (just run it on command line)

diff --git a/spotbugs/src/main/java/edu/umd/cs/findbugs/detect/FindOverridableMethodCall.java b/spotbugs/src/main/java/edu/umd/cs/findbugs/detect/FindOverridableMethodCall.java
index b96fe8b..d1f87de 100644
--- a/spotbugs/src/main/java/edu/umd/cs/findbugs/detect/FindOverridableMethodCall.java
+++ b/spotbugs/src/main/java/edu/umd/cs/findbugs/detect/FindOverridableMethodCall.java
@@ -41,2 +41,3 @@
 import org.apache.bcel.classfile.Method;
+import org.apache.bcel.classfile.Visitor;
 
@@ -99,3 +100,24 @@
 
-    @Override
+    private static void printName(String mName) {
+        char[] name = mName.toCharArray();
+        System.out.println("Name: '" + mName + "'");
+        for (char c : name) {
+            System.out.println("" + c + " : " + (int) c);
+        }
+    }
+
+    public static void main(String[] args) {
+        java.lang.reflect.Method method = Arrays.asList(Visitor.class.getMethods()).stream()
+                .filter(m -> m.getName().startsWith("visitBootstrapMethods")).findFirst().get();
+        String name = method.getName();
+        printName(name);
+
+        method = Arrays.asList(FindOverridableMethodCall.class.getMethods()).stream()
+                .filter(m -> m.getName().startsWith("visitBootstrapMethods")).findFirst().get();
+        String name2 = method.getName();
+        printName(name2);
+        System.out.println("Equal names? : " + name.equals(name2));
+        System.out.println("Ends with '\\u200b' ? : " + name2.endsWith("" + '\u200b'));
+    }
+
     public void visitBootstrapMethods​(BootstrapMethods obj) {

Output in Eclipse (note the last 8203 character printed):

Name: 'visitBootstrapMethods'
v : 118
i : 105
s : 115
i : 105
t : 116
B : 66
o : 111
o : 111
t : 116
s : 115
t : 116
r : 114
a : 97
p : 112
M : 77
e : 101
t : 116
h : 104
o : 111
d : 100
s : 115
Name: 'visitBootstrapMethods​'
v : 118
i : 105
s : 115
i : 105
t : 116
B : 66
o : 111
o : 111
t : 116
s : 115
t : 116
r : 114
a : 97
p : 112
M : 77
e : 101
t : 116
h : 104
o : 111
d : 100
s : 115
​ : 8203
Equal names? : false
Ends with '\u200b' ? : true

[iloveeclipse]

This can find all non-ascii characters in java code in the repo

find -name *.java  -exec grep --color='auto' -P -n "[^[:ascii:]]" {} +
./spotbugs/src/main/java/edu/umd/cs/findbugs/detect/FindOverridableMethodCall.java:101:    public void visitBootstrapMethodsâ(BootstrapMethods obj) {
...
some other not critical code locations 
...