Tomcat源码分析之getParameter(String)与getQueryString()

01

final

StringBuffer fileData = 

new

StringBuffer(

1000

);

02

03

final

BufferedReader reader = 

new

BufferedReader(

04

05

new

FileReader(

"fileIn.txt"

));

06

07

char

[] buf = 

new

char

[

1024

];

08

09

int

numRead = 

0

;

10

11

while

((numRead = reader.read(buf)) != -

1

)

12

13

{

14

15

final

String readData = String.valueOf(buf, 

0

, numRead);

16

17

fileData.append(readData);

18

19

buf = 

new

char

[

1024

];

20

21

}

22

23

reader.close();

24

25

String mergedContent = fileData.toString();

26

27

mergedContent = mergedContent.replaceAll(

"\\<.*?>"

, 

" "

);

28

29

mergedContent = mergedContent.replaceAll(

"\\r\\n|\\r|\\n"

, 

" "

);

30

31

final

BufferedWriter out = 

new

BufferedWriter(

32

33

new

OutputStreamWriter(

34

35

new

FileOutputStream(

"fileOut.txt"

)));

36

37

final

HashMap<String, String> wordsMap = 

new

HashMap<String, String>();

38

39

final

String test[] = mergedContent.split(

" "

);

40

41

for

(

final

String string : test)

42

43

{

44

wordsMap.put(string, string);

45

46

}

47

for

(

final

String string : wordsMap.values())

48

49

{

50

out.write(string + 

"\n"

);

51

52

}

53

out.close();

01

...

02

03

for

(

final

String string : test)

04

{

05

out.write(string + 

"\n"

);

06

//wordsMap.put(string, string);

07

08

}

09

10

//for (final String string : wordsMap.values())

11

12

//{

13

14

//  out.write(string + "\n");

15

16

//}

17

out.close();

01

@Override

02

protected

void

doGet(HttpServletRequest req, HttpServletResponse resp)

03

throws

ServletException, IOException {

04

//System.out.println(req);

05

System.out.println(

"Request::getParameter(addr) is: "

+ req.getParameter(

"addr"

));

06

String queryString = req.getQueryString();

07

System.out.println(

"queryString is: "

+queryString);

08

String[]  params = queryString.split(

"[=]"

);

09

10

Map<String, String> map = 

new

HashMap<String, String>();

11

12

map.put(params[

0

], params[

1

]);

13

System.out.println(

"Map::get(addr) is: "

+map.get(params[

0

]));

14

return

;

15

}

1

<Connector port=

"8080"

protocol=

"HTTP/1.1"

2

connectionTimeout=

"20000"

3

redirectPort=

"8443"

4

URIEncoding=

"utf-8"

5

/>

1

-RequestFacade::getQueryString()

2

3

-Request::getQueryString()

4

5

-org.apache.coyote.Request::queryString()::toString()

1

@Override

2

public

String getQueryString() {

3

if

(request == 

null

) {

4

throw

new

IllegalStateException(

5

sm.getString(

"requestFacade.nullRequest"

));

6

}

7

return

request.getQueryString();

8

}

01

/**

02

03

* Return the query string associated with this request.

04

05

*/

06

07

@Override

08

public

String getQueryString() {

09

return

coyoteRequest.queryString().toString();

10

}

1

public

MessageBytes queryString() {

2

return

queryMB;

3

}

1

private

MessageBytes queryMB = MessageBytes.newInstance();

1

public

MessageBytes queryString() {

2

return

queryMB;

3

}

1

public

void

recycle() {

2

….

3

queryMB.recycle();

4

….

5

}

1

public

Request() {

2

parameters.setQuery(queryMB);

3

parameters.setURLDecoder(urlDecoder);

4

}

01

/**

02

* Read the request line. This function is meant to be used during the 

03

* HTTP request header parsing. Do NOT attempt to read the request body 

04

* using it.

05

*

06

* @throws IOException If an exception occurs during the underlying socket

07

* read operations, or if the given buffer is not big enough to accommodate

08

* the whole line.

09

* @return true if data is properly fed; false if no data is available 

10

* immediately and thread should be freed

11

*/

12

@Override

13

public

boolean

parseRequestLine(

boolean

useAvailableData)

14

throws

IOException {

15

….

16

if

(questionPos >= 

0

) {

17

request.queryString().setBytes(buf, questionPos + 

1

,

18

end - questionPos - 

1

);

19

request.requestURI().setBytes(buf, start, questionPos - start);

20

} 

else

{

21

request.requestURI().setBytes(buf, start, end - start);

22

}

23

….

24

}

1

request.queryString().setBytes(buf, questionPos + 

1

,

2

end - questionPos - 

1

);

01

-RequestFacade::getParameter(String)

02

03

-Request::getParameter(String)

04

05

-Request::parseParameters()

06

07

-coyote.Request::getParameters()

08

09

-Parameters::setLimit(

int

)

10

11

-Parameters::setEncoding(String)

12

13

-Parameters::handleQueryParameters()

14

15

-decodedQuery.duplicate(MessageBytes)

16

17

-Parameters::processParameters(MessageBytes, String)

18

19

-Parameters::processParameters(

byte

[],

int

,

int

，String)

20

-coyote.Request::getParameters()::getParameter(String)

21

22

-Parameters::paramHashValues.get(String)

01

// -------------------- Processing --------------------

02

/** Process the query string into parameters

03

*/

04

public

void

handleQueryParameters() {

05

...

06

try

{

07

decodedQuery.duplicate( queryMB );

08

} 

catch

(IOException e) {

09

// Can't happen, as decodedQuery can't overflow

10

e.printStackTrace();

11

}

12

processParameters( decodedQuery, queryStringEncoding );

13

}

1

public

void

processParameters( MessageBytes data, String encoding ) {

2

...

3

ByteChunk bc=data.getByteChunk();

4

processParameters( bc.getBytes(), bc.getOffset(),

5

bc.getLength(), getCharset(encoding));

6

}

01

// -------------------- Parameter parsing --------------------

02

// we are called from a single thread - we can do it the hard way

03

// if needed

04

ByteChunk tmpName=

new

ByteChunk();

05

ByteChunk tmpValue=

new

ByteChunk();

06

private

final

ByteChunk origName=

new

ByteChunk();

07

private

final

ByteChunk origValue=

new

ByteChunk();

08

CharChunk tmpNameC=

new

CharChunk(

1024

);

09

public

static

final

String DEFAULT_ENCODING = 

"ISO-8859-1"

;

10

private

static

final

Charset DEFAULT_CHARSET =

11

Charset.forName(DEFAULT_ENCODING);

1

public

static

final

String DEFAULT_ENCODING = 

"ISO-8859-1"

;

01

pos: 开始位置

02

end: 结束位置

03

while

(pos < end)

04

nameStart: 初始化为pos，参数名称开始位置

05

nameEnd: 初始化为-

1

，参数名称结束位置，通过nameStart和nameEnd可获得参数名称

06

valueStart: 初始化为-

1

，参数值开始位置

07

valueEnd: 初始化为-

1

,参数值结束位置，通过valueStart和valueEnd可获得参数值

08

parsingName：布尔类型，初始化为

true

，用来标识是否正在解析名称

09

parameterComplete: 布尔类型，初始化为

false

，用来标识一个parameter是否解析完成

10

11

do

12

swtich(当前位置pos对应的字节)

13

'='

:

14

是否正在解析参数名称，是则nameEnd = pos, parsingName = 

false

, pos++, valueStart = pos;

15

否则pos++;

16

'&'

:

17

是否正在解析参数名称，如果是，则nameEnd=pos,否则valueEnd = pos, pos++;

18

parameterComplete=ture参数整体解析完成

19

pos++;

20

default

:

21

pos++;

22

while

(parameter未解析完成 且 pos < end)

23

24

if

(pos == end)

25

if

(nameEnd == -

1

)

26

nameEnd = pos;

27

if

(valueStart >　-

1

&& valueEnd == -

1

)

28

valueEnd = pos;

29

end 

while

01

int

pos = start;

02

int

end = start + len;

03

04

while

(pos < end) {

05

int

nameStart = pos;

06

int

nameEnd = -

1

;

07

int

valueStart = -

1

;

08

int

valueEnd = -

1

;

09

10

boolean

parsingName = 

true

;

11

boolean

decodeName = 

false

;

12

boolean

decodeValue = 

false

;

13

boolean

parameterComplete = 

false

;

14

15

do

{

16

switch

(bytes[pos]) {

17

case

'='

:

18

if

(parsingName) {

19

// Name finished. Value starts from next character

20

nameEnd = pos;

21

parsingName = 

false

;

22

valueStart = ++pos;

23

} 

else

{

24

// Equals character in value

25

pos++;

26

}

27

break

;

28

case

'&'

:

29

if

(parsingName) {

30

// Name finished. No value.

31

nameEnd = pos;

32

} 

else

{

33

// Value finished

34

valueEnd  = pos;

35

}

36

parameterComplete = 

true

;

37

pos++;

38

break

;

39

case

'%'

:

40

case

'+'

:

41

// Decoding required

42

if

(parsingName) {

43

decodeName = 

true

;

44

} 

else

{

45

decodeValue = 

true

;

46

}

47

pos ++;

48

break

;

49

default

:

50

pos ++;

51

break

;

52

}

53

} 

while

(!parameterComplete && pos < end);

54

55

if

(pos == end) {

56

if

(nameEnd == -

1

) {

57

nameEnd = pos;

58

} 

else

if

(valueStart > -

1

&& valueEnd == -

1

){

59

valueEnd = pos;

60

}

61

}

62

...

63

}

01

tmpName.setBytes(bytes, nameStart, nameEnd - nameStart);

02

if

(valueStart >= 

0

) {

03

tmpValue.setBytes(bytes, valueStart, valueEnd - valueStart);

04

} 

else

{

05

tmpValue.setBytes(bytes, 

0

, 

0

);

06

}

07

08

try

{

09

String name;

10

String value;

11

12

if

(decodeName) {

13

urlDecode(tmpName);

14

}

15

tmpName.setCharset(charset);

16

name = tmpName.toString();

17

18

if

(valueStart >= 

0

) {

19

if

(decodeValue) {

20

urlDecode(tmpValue);

21

}

22

tmpValue.setCharset(charset);

23

value = tmpValue.toString();

24

} 

else

{

25

value = 

""

;

26

}

27

28

try

{

29

addParameter(name, value);

30

} 

catch

(IllegalStateException ise) { <span></span>

// Hitting limit stops processing further params but does

31

...

32

}

33

} 

catch

(IOException e) {

34

...

35

}

36

37

tmpName.recycle();

38

tmpValue.recycle();