src/org/nutz/repo/org/objectweb/asm/ClassWriter.java
Item newMethodTypeItem(final String methodDesc) {
        key2.set(MTYPE, methodDesc, null, null);
        Item result = get(key2);
        if (result == null) {
            pool.put12(MTYPE, newUTF8(methodDesc));
            result = new Item(index++, key2);
            put(result);
        }
        return result;
    }
Item newMethodTypeItem(final String methodDesc) {
        key2.set(MTYPE, methodDesc, null, null);
        Item result = get(key2);
        if (result == null) {
            pool.put12(MTYPE, newUTF8(methodDesc));
            result = new Item(index++, key2);
            put(result);
        }
        return result;
    }
Adds a method type reference to the constant pool of the class being
build. Does nothing if the constant pool already contains a similar item.
<i>This method is intended for {@link Attribute} sub classes, and is
normally not needed by class generators or adapters.</i>

@param methodDesc
method descriptor of the method type.
@return a new or already existing method type reference item.