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RepeatingAlarm / src / com.example.android.common / logger /

LogView.java

       
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        /*
       
       
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        * Copyright (C) 2013 The Android Open Source Project
       
       
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        *
       
       
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        * Licensed under the Apache License, Version 2.0 (the "License");
       
       
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        * you may not use this file except in compliance with the License.
       
       
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        * You may obtain a copy of the License at
       
       
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        *
       
       
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        *      http://www.apache.org/licenses/LICENSE-2.0
       
       
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        *
       
       
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        * Unless required by applicable law or agreed to in writing, software
       
       
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        * distributed under the License is distributed on an "AS IS" BASIS,
       
       
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        * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
       
       
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        * See the License for the specific language governing permissions and
       
       
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        * limitations under the License.
       
       
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        */
       
       
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        package com.example.android.common.logger;
       
       
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        import android.app.Activity;
       
       
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        import android.content.Context;
       
       
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        import android.util.*;
       
       
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        import android.widget.TextView;
       
       
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        /** Simple TextView which is used to output log data received through the LogNode interface.
       
       
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        */
       
       
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        public class LogView extends TextView implements LogNode {
       
       
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        public LogView(Context context) {
       
       
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        super(context);
       
       
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        }
       
       
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        public LogView(Context context, AttributeSet attrs) {
       
       
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        super(context, attrs);
       
       
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        }
       
       
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        public LogView(Context context, AttributeSet attrs, int defStyle) {
       
       
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        super(context, attrs, defStyle);
       
       
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        }
       
       
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        /**
       
       
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        * Formats the log data and prints it out to the LogView.
       
       
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        * @param priority Log level of the data being logged.  Verbose, Error, etc.
       
       
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        * @param tag Tag for for the log data.  Can be used to organize log statements.
       
       
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        * @param msg The actual message to be logged. The actual message to be logged.
       
       
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        * @param tr If an exception was thrown, this can be sent along for the logging facilities
       
       
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        *           to extract and print useful information.
       
       
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        */
       
       
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        @Override
       
       
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        public void println(int priority, String tag, String msg, Throwable tr) {
       
       
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        String priorityStr = null;
       
       
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        // For the purposes of this View, we want to print the priority as readable text.
       
       
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        switch(priority) {
       
       
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        case android.util.Log.VERBOSE:
       
       
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        priorityStr = "VERBOSE";
       
       
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        break;
       
       
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        case android.util.Log.DEBUG:
       
       
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        priorityStr = "DEBUG";
       
       
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        break;
       
       
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        case android.util.Log.INFO:
       
       
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        priorityStr = "INFO";
       
       
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        break;
       
       
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        case android.util.Log.WARN:
       
       
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        priorityStr = "WARN";
       
       
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        break;
       
       
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        case android.util.Log.ERROR:
       
       
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        priorityStr = "ERROR";
       
       
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        break;
       
       
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        case android.util.Log.ASSERT:
       
       
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        priorityStr = "ASSERT";
       
       
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        break;
       
       
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        default:
       
       
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        break;
       
       
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        }
       
       
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        // Handily, the Log class has a facility for converting a stack trace into a usable string.
       
       
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        String exceptionStr = null;
       
       
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        if (tr != null) {
       
       
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        exceptionStr = android.util.Log.getStackTraceString(tr);
       
       
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        }
       
       
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        // Take the priority, tag, message, and exception, and concatenate as necessary
       
       
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        // into one usable line of text.
       
       
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        final StringBuilder outputBuilder = new StringBuilder();
       
       
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        String delimiter = "\t";
       
       
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        appendIfNotNull(outputBuilder, priorityStr, delimiter);
       
       
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        appendIfNotNull(outputBuilder, tag, delimiter);
       
       
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        appendIfNotNull(outputBuilder, msg, delimiter);
       
       
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        appendIfNotNull(outputBuilder, exceptionStr, delimiter);
       
       
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        // In case this was originally called from an AsyncTask or some other off-UI thread,
       
       
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        // make sure the update occurs within the UI thread.
       
       
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        ((Activity) getContext()).runOnUiThread( (new Thread(new Runnable() {
       
       
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        @Override
       
       
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        public void run() {
       
       
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        // Display the text we just generated within the LogView.
       
       
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        appendToLog(outputBuilder.toString());
       
       
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        }
       
       
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        })));
       
       
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        if (mNext != null) {
       
       
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        mNext.println(priority, tag, msg, tr);
       
       
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        }
       
       
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        }
       
       
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        public LogNode getNext() {
       
       
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        return mNext;
       
       
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        }
       
       
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        public void setNext(LogNode node) {
       
       
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        mNext = node;
       
       
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        }
       
       
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        /** Takes a string and adds to it, with a separator, if the bit to be added isn't null. Since
       
       
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        * the logger takes so many arguments that might be null, this method helps cut out some of the
       
       
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        * agonizing tedium of writing the same 3 lines over and over.
       
       
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        * @param source StringBuilder containing the text to append to.
       
       
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        * @param addStr The String to append
       
       
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        * @param delimiter The String to separate the source and appended strings. A tab or comma,
       
       
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        *                  for instance.
       
       
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        * @return The fully concatenated String as a StringBuilder
       
       
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        */
       
       
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        private StringBuilder appendIfNotNull(StringBuilder source, String addStr, String delimiter) {
       
       
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        if (addStr != null) {
       
       
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        if (addStr.length() == 0) {
       
       
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        delimiter = "";
       
       
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        }
       
       
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        return source.append(addStr).append(delimiter);
       
       
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        }
       
       
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        return source;
       
       
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        }
       
       
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        // The next LogNode in the chain.
       
       
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        LogNode mNext;
       
       
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        /** Outputs the string as a new line of log data in the LogView. */
       
       
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        public void appendToLog(String s) {
       
       
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        append("\n" + s);
       
       
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        }
       
       
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        }