我在学习RxJava2时遇到OnErrorNotImplementedException。我了解到这种异常的发生是由于没有为订阅者实现错误处理程序。所以，我想除了onError方法之外，为什么它不存在。为什么呢？
答案 0 :(得分：0)
from bokeh.plotting import figure
from bokeh.models import ColumnDataSource, CustomJS, CDSView, CustomJSFilter, HoverTool
from bokeh.models.widgets import CheckboxButtonGroup
from bokeh.io import show, output_notebook
from bokeh.palettes import Set1
from bokeh.transform import factor_cmap
from bokeh.layouts import widgetbox, layout
import pandas as pd
import numpy as np
import datetime as dt
from itertools import cycle, islice
output_notebook()
N = 24
start_date = dt.date(2016,1,1)
nbdays = int(365 / N)
df = pd.DataFrame({'Date': [start_date + dt.timedelta(days=i*nbdays) for i in range(1,N+1)],
'Rating': [(100/N)*i for i in range(1,N+1)],
'Plot': list(islice(cycle(range(1, 9)), 0, N)),
'Treatment': list(islice(cycle(range(1, 7)), 0, N)),
'Trial': list(islice(cycle(range(1, 4)), 0, N)),
'Name': list(islice(cycle("ABCDEF"), 0, N)),
'Target': list(islice(cycle("JKLMNOP"), 0, N)),
'Part': list(islice(cycle("WXYZ"), 0, N))
})
columns = 'Plot', 'Trial', 'Name', 'Target', 'Part'
unique_items = [df[col].unique() for col in columns]
df["Treatment"] = df["Treatment"].astype(str)
source = ColumnDataSource(data=df)
dummy_source = ColumnDataSource(data={"x":[], "y":[]})
hover = HoverTool(tooltips=[('Date', '@Date{%d/%m/%Y}')] + [(column, '@'+column)
for column in columns], formatters={
'Date': 'datetime', # use 'datetime' formatter for 'Date' field
})
p = figure(x_axis_type="datetime", tools=[hover])
color = factor_cmap("Treatment", Set1[9], df.Treatment.unique())
for i, label in enumerate(df.Treatment.unique()):
dummy_circle = p.circle(x="x", y="y", source=dummy_source, legend="Treatment {}".format(label), color=Set1[9][i])
dummy_circle.tags = [label]
p.legend.location = "bottom_right"
p.legend.click_policy = "hide"
def source_change(source=source):
source.change.emit()
callback_source_change = CustomJS.from_py_func(source_change)
for item in p.legend[0].items:
item.renderers[0].js_on_change("visible", callback_source_change)
controls = [CheckboxButtonGroup(labels=items.astype(str).tolist(), active=list(range(len(items)))) for items in unique_items]
widgets = widgetbox(*controls)
for name, control in zip(columns, controls):
control.tags = [name]
def func_filter(source=source, legend=p.legend[0], widgets=widgets):
window.widgets = widgets
visible_treatments = [item.renderers[0].tags for item in legend.items if item.renderers[0].visible]
date = source.data['Date']
treatments = source.data['Treatment']
res = []
selectors = {}
for widget in widgets.children:
col = widget.tags[0]
selectors[col] = dict([(widget.labels[i], i) for i in widget.active])
for i in range(len(date)):
flag = treatments[i] in visible_treatments
for key, val in selectors.items():
if source.data[key][i] not in val:
flag = False
break
res.append(flag)
return res
view = CDSView(source=source, filters=[CustomJSFilter.from_py_func(func_filter)])
p.circle(x='Date', y='Rating', source=source, view=view, line_color=color, fill_color=color)
for control in controls:
control.js_on_change("active", callback_source_change)
show(layout([[p, widgets]]))
方法不会消耗错误，最终会抛出订阅者。在这种情况下，如果您未处理订阅者，则会抛出doOnError。
以下方法将消耗OnErrorNotImplementedException方法中提到的错误。
方法1：
subscribe方法2：
Observable.just(new Object())
.doOnNext(o -> { /* /* This method catches the on next but doesn't consume it. */})
.doOnComplete(() -> { /* test */})
.doOnError(throwable -> {/* This method catches the error but doesn't consume it. */})
.subscribe(o ->
{/* success */}
,
throwable -> {/* error */} // here error will be consumed at the end
);
总的来说，你必须消耗错误，否则你将面临同样的错误。