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/*
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* Copyright (C) 2012 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.util.Log;
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/**
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* Helper class which wraps Android's native Log utility in the Logger interface. This way
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* normal DDMS output can be one of the many targets receiving and outputting logs simultaneously.
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*/
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public class LogWrapper implements LogNode {
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// For piping: The next node to receive Log data after this one has done its work.
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private LogNode mNext;
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/**
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* Returns the next LogNode in the linked list.
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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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/**
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* Sets the LogNode data will be sent to..
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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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/**
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* Prints data out to the console using Android's native log mechanism.
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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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// There actually are log methods that don't take a msg parameter. For now,
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// if that's the case, just convert null to the empty string and move on.
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String useMsg = msg;
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if (useMsg == null) {
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useMsg = "";
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}
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// If an exeption was provided, convert that exception to a usable string and attach
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// it to the end of the msg method.
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if (tr != null) {
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msg += "\n" + Log.getStackTraceString(tr);
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}
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// This is functionally identical to Log.x(tag, useMsg);
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// For instance, if priority were Log.VERBOSE, this would be the same as Log.v(tag, useMsg)
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Log.println(priority, tag, useMsg);
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// If this isn't the last node in the chain, move things along.
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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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}