2023年11月25日

Java代写 | CS300 Spring 2020 Programming Project

本次Java代写是完成一个多线程通信系统
CS300 Spring 2020

The passage processor will read a series of passage file names from passages.txt. A thread will be created for each  
passage that builds Trie with words in the passage text, receives requests for longest word searches, searches the  
trie for the longest word and asynchronously returns the longest word. The Passage Processor will read each  
prefix request from the System V ipc queue using a Java Native Call, sends the requests to each worker, retrieves  
responses from each worker and sends them back to the search manager via the system V queue. For each prefix  
request, the trie should be searched for the longest word that starts with that prefix. In the case that a word is  
found, the longest word will be sent to the SearchManager via the System V ipc queue via a Java Native call. The  
response will include the prefix id, the passage id, the passage name, the number of passages, present = 1, and the  
longest word. In the case that the prefix is not found, the response will include the prefix id and present = 0.  
Format: java -cp . -Djava.library.path=. edu.cs300.TextSamples  
[email protected]: java -cp . -Djava.library.path=. edu.cs300.TextSamples 2>/dev/null  
Worker-0 (Sense_And_Sensibility.txt) thread started …  
Worker-1 (Mansfield_Park.txt) thread started …  
Worker-2 (The_Call_Of_The_Wild.txt) thread started …  
Worker-4 (Peter_Pan.txt) thread started …  
**prefix(1) con received  
Worker-2 1:con ==> not found  
Worker-3 (Tale_Of_Two_Cities.txt) thread started …  
Worker-3 1:con ==> not found  
msgsnd Reply 2 of 5 on 1:con from The_Call_Of_The_Wild.txt present=0 lw=—-(len=4) msglen=144  
msgsnd Reply 3 of 5 on 1:con from Tale_Of_Two_Cities.txt present=0 lw=—-(len=4) msglen=144  
Worker-1 1:con ==> contemptible  
Worker-4 1:con ==> conspicuous  
msgsnd Reply 1 of 5 on 1:con from Mansfield_Park.txt present=1 lw=contemptible(len=12) msglen=144  
msgsnd Reply 4 of 5 on 1:con from Peter_Pan.txt present=1 lw=conspicuous(len=11) msglen=144  
Worker-0 1:con ==> constant  
msgsnd Reply 0 of 5 on 1:con from Sense_And_Sensibility.txt present=1 lw=constant(len=8)  
msglen=144  
**prefix(2) pre received  
Worker-2 2:pre ==> not found  
Worker-0 2:pre ==> not found  
msgsnd Reply 2 of 5 on 2:pre from The_Call_Of_The_Wild.txt present=0 lw=—-(len=4) msglen=144  
msgsnd Reply 0 of 5 on 2:pre from Sense_And_Sensibility.txt present=0 lw=—-(len=4) msglen=144  
Worker-4 2:pre ==> not found  
msgsnd Reply 4 of 5 on 2:pre from Peter_Pan.txt present=0 lw=—-(len=4) msglen=144  
Worker-1 2:pre ==> predict  
msgsnd Reply 1 of 5 on 2:pre from Mansfield_Park.txt present=1 lw=predict(len=7) msglen=144  
Worker-3 2:pre ==> preserves  
msgsnd Reply 3 of 5 on 2:pre from Tale_Of_Two_Cities.txt present=1 lw=preserves(len=9) msglen=144  
**prefix(3) wor received  
Worker-1 3:wor ==> world  
Worker-3 3:wor ==> worst  
Worker-0 3:wor ==> not found  
Worker-2 3:wor ==> not found  
msgsnd Reply 1 of 5 on 3:wor from Mansfield_Park.txt present=1 lw=world(len=5) msglen=144  
Worker-4 3:wor ==> not found  
msgsnd Reply 3 of 5 on 3:wor from Tale_Of_Two_Cities.txt present=1 lw=worst(len=5) msglen=144  
msgsnd Reply 0 of 5 on 3:wor from Sense_And_Sensibility.txt present=0 lw=—-(len=4) msglen=144  
msgsnd Reply 2 of 5 on 3:wor from The_Call_Of_The_Wild.txt present=0 lw=—-(len=4) msglen=144  
msgsnd Reply 4 of 5 on 3:wor from Peter_Pan.txt present=0 lw=—-(len=4) msglen=144  
**prefix(0) received  
Terminating …  
Search Manager requirements  
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Must be written in C  
Numeric parameter denoting delay will be present and an integer; if it is zero, then use no delay  
At least one prefix will be provided (may not be valid)  
Only process prefixes are at least 3 characters should be processed  
Only one prefix should be processed at a time. Once all the results on a prefix are returned, the next can be  
sent to the passage processor  
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Send a prefix message with a zero id to notify the passage processor to complete

Passage processor requirements  
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Written in Java with the main function in edu.cs300.PassageProcessor.java  
Read passage file names from passages.txt in root directory (hardcode the name)  
Read contents of each passages file in the root directory  
General criteria  
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Programs will only be graded on cs426.ua.edu  
Late submissions will not be accepted  
Input criteria:  
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o
o
o
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Prefixes-at least three characters long and no longer that 20 characters  
Text Passages-Unlimited number of passages  
Longest word-Maximum length 100 characters  
Prefix Request -Unlimited number of requests  
Text Processing-Ignore punctuation, only store words. Words with punctuation in them should  
be ignored.  
o
Passage Name should be the first 30 characters of the filename  
•
The System V message queue requires an existing file and integer to create a unique queue name. You should  
create a file using your crimson id in your home directory. Use queue_ids.h header file to create a constant  
string that holds the path to the queue and a constant integer to hold the day of your birthday.
Place files in the directory structure below (matches sample github)  
.
── _passages.txt  
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└
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── _Pride_And_Prejudice.txt  
── _Mansfield_Park.txt.txt  
── _The_Call_Of_The_Wild.txt  
── _Tale_Of_Two_Cities.txt  
── _Peter_Pan.txt  
── _edu_cs300_MessageJNI.h  
── _queue_ids.h  
── _longest_word_search.h  
── _searchmanager.c  
── _system5msg.c  
── _<Additional supporting C files>.c  
── _<Additional supporting header files>.c  
── _edu  
└── cs300  
└── SearchRequest.java  
└── MessageJNI.java  
└── ParallelTextSearch.java  
└── Worker.java  
└── PassageProcessor.java  
└── <Additional Supporting Java Source>.java  
── _ CtCILibrary  
├── Trie.java  
└── TrieNode.java  
── _Makefile //if commands other than those provided are needed to build executables or dynamic library  
── _readme.md  
Hints:  
•
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Use blocking msgrcv  
Wrap search manager msgrcv in a while loop since SIGINT will cause the msgrcv to return with no message

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Create two SIGINT handlers: one that gives a starting status that does not include any shared information and  
a 2 handler that returns shared (protected) information  
nd  
longest_word_search.h notes  
#define WORD_LENGTH 100+1  
#define PASSAGE_NAME_LENGTH 30+1  
// Declare the message structure  
*** message struct for sending in msgsnd_pr.c and receive in  
system5msg
*
*
** type should be set 1 for sending and receiving  
** total 4 plus length of prefix plus 1  
typedef struct prefixbuf {  
//set to 1 and corresponds to type in parm 4-msgrcv(msqid, &rbuf, WORD_LENGTH, 1, 0)  
long mtype; //not in byte count  
int id; //4 bytes  
char prefix[WORD_LENGTH]; //4 bytes in the case of a three letter prefix and a null  
}
prefix_buf;  
*** message struct for sending in msgsnd_pr.c and receive in  
system5msg(Java_edu_cs300_MessageJNI_writeLongestWordResponseMsg)  
*
*
** type should be set 2 for sending and receiving  
**total 144 bytes  
typedef struct foundbuf {  
/
/
/set to 2 and corresponds to type in parm 4-msgrcv(msqid, &rbuf, WORD_LENGTH, 2, 0)  
/ in msgrcv_lwr.c  
long mtype; //not in byte count  
int index; //index of response-4 bytes  
int count; //total excerpts available-4 bytes  
int present; //0 if not found; 1 if found-4 bytes  
char location_description[PASSAGE_NAME_LENGTH]; //31 bytes  
char longest_word[WORD_LENGTH]; //101 bytes  
}
response_buf;  
Parameters  
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Minimize resource usage (do not hardcode any values other than given above)  
Do not assume any ordering of the message retrieval  
Maximize parallel processing  
Appropriately protect data structures as needed  
Minimize use of global variables (don’t use as a mechanism to avoid passing parameters)  
Synchronize calls to msgsnd and msgrcv  
Free any allocated memory; join any threads  

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Do not remove IPC queue when done  
Message queue key should be your crimson id  
Programs should be coded in C language (C99 standard) and will be compiled and tested on  
cs426.ua.edu. If you choose to program on another system, give yourself enough time verify it works on  
cs426. No other system will be used to test your code. May need _GNU_SOURCE switch.  
You should use the pthreads library for threading. You can use mutexes or condition variables from the  
pthreads library and/or semaphores from the posix library.  
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Appropriate data structures should be selected based on your knowledge of data structures (CS201, etc).  
Algorithms should be efficient and appropriate. This program should demonstrate not only your  
understanding of process synchronization but your ability to design a program appropriately  
No sleeps other than sleep between sending prefix requests driven by command line argument  
Use #ifdef DEBUG to remove/add debug print statements based on compilation (-DDEBUG=0 or –  
DDEBUG=1)