Atitit. Annotation parsing (1)---------lexical analysis Attilax summarizing Java. net__.net

Atitit. Annotation parsing (1)---------Lexical Analysis Attilax summary java. net

1. Application scenario::: Because to use the UI annotation 1

2. The process is as follows::: Lexical analysis (generate token flow) >>>> Grammar analysis (generate AST) >> explain execution ... 2

3. Lexical analysis of the framework, ANTLR 2

4. FSM state machine///Switch 2

5. The word stream must be recognized as reserved words, identifiers (variables), constants, operators (operator) and bounds of the five categories 2

5.1. Operator (operator)::: 2

5.2.4. The boundary character: ";" semicolon, "{}" curly braces, single quotes, double quotes 3

6. Define Context 3

7. Note Name Atstate processing 4

8. Split character processing Doublequoestate 5

9. Operator (operator): processing Leftbrackt 5

10. Call result, output token stream 6

GitHub Open Source Project Atiannointerpreter 7

1. Application scenario::: Because you want to use a UI annotation

String s = "@QueryAdptr (sqlwhere=\" clo1= ' @p ' ", prop2=\" v2\ ") @Nofilt";

Creating an environment

So, to parse the annotations ...

Online horse,, son can get the realization of the LAN ....

If the Java source annotation can be read by using the Java API ...

The annotations in HTML are implemented by the self-implementation LAN.

Author:: Old Wow's paw Attilax Airon, email:1466519819@qq.com

Reprint please indicate the source: Http://blog.csdn.net/attilax

2. The process is as follows::: Lexical analysis (generate token flow) >>>> Grammar analysis (generate AST) >> explain execution ...

3. Lexical analysis of the framework, ANTLR

Use tired hang, difficult. Son good, write his own blue ...

4. Fsm state machine///switch

Use an FSM to replace the switch mode ...

Oo language can also be done using state mode ...

5. Word flow must be recognized as reserved words, identifiers (variables), constants, operators (operators) and bounds of the five categories

5.1. operator (operator) :::

() []->.

? :

Conditions

From right to left

() []->.

Parentheses (functions, etc.), array, two struct members access

From left to right

,	Commas (order)
+ -	Plus, minus	From left to right

Parentheses, spin brackets, equals

Reference

Compiler diy--Lexical analysis-godlike-Blog channel-CSDN.NET.htm

operator to use a state to describe ... 5.2 4. Operator: ";" semicolon, "{}" curly braces, single quotes, double quotes

The boundary character in the processing time son, Lin Bar filtration ...

6. Define context

Design Description::: Use keystate to define the operation state,,, keystate changes have state internal implementation

State uses to describe the status of each character ..., the modification of this condition has a context to implement.

Class Annopasercontext extends Context {

Holds an object instance of State type

public state State;

public state lastkeystate;

Public Object Rzt;

Public Token curtoken=new Token ();

Public list<token> tokenlist=new arraylist<token> ();

public Char Curchar;

Public char[] Chararr;

public int curcharindex;

public void SetState (state state) {

This.state = State;

}

/**

* User-Interested interface method

*/

public void request (String sampleparameter) {

State=new normalstate ();

if (Curcharindex>=sampleparameter.length ())

{

State=new finishstate ();

State.handle (Sampleparameter, this);

Return

}

Curchar=chararr[curcharindex];

def Todox if to swithc OAO

if (curchar== ' @ ')//keyword

State=new atstate ();

if (curchar== ' ")//splittor Word

State=new doublequoestate ();

if (curchar== ')//op Word

State=new Leftbrackt ();

if (curchar== ') ")

State=new Rightbrackt ();

if (curchar== ' = ')

State=new eqxstate ();

if (curchar== ', ')

State=new commastate ();

Transfer the state to handle

State.handle (Sampleparameter, this);

}

7. annotation name atstate processing

Atstate implements State {

@Override

public void handle (String Sampleparameter, context context) {

Annopasercontext ctt= (annopasercontext) context;

Char Curchar=ctt.curchar;

if (ctt.lastkeystate instanceof inistate | | ctt.lastkeystate instanceof rightbrackt)

{

Token tk=new Token ();

Tk.value=ctt.curtoken.value;

Ctt.tokenList.add (TK);

Ctt.curtoken=new Token ();

Ctt.lastkeystate=new atstate ();

}

Ctt.curtoken.value+=curchar;

ctt.curcharindex++;

} 8. Split character processing doublequoestate

Doublequoestate implements State {

@Override

public void handle (String Sampleparameter, context context) {

Annopasercontext ctt= (annopasercontext) context;

Char Curchar=ctt.curchar;

Token tk=new Token ();

Tk.value=ctt.curtoken.value;

Ctt.tokenList.add (TK);

Ctt.tokenList.add (New Token () {this.value= ",";}});

Ctt.curtoken=new Token ();

Ctt.curtoken.value+=curchar;

ctt.curcharindex++;

Ctt.lastkeystate=new doublequoestate ();

}

9. operator (operator): processing leftbrackt

Leftbrackt implements State {

@Override

public void handle (String Sampleparameter, context context) {

Annopasercontext ctt= (annopasercontext) context;

Char Curchar=ctt.curchar;

Token tk=new Token ();

Tk.value=ctt.curtoken.value;

Ctt.tokenList.add (TK);

Ctt.tokenList.add (New Token () {this.value= "(";}});

Ctt.curtoken=new Token ();

Ctt.curtoken.value+=curchar;

ctt.curcharindex++;

Ctt.lastkeystate=new Leftbrackt ();

}

10. Call result, output token stream

@QueryAdptr

(

Sqlwhere

=

clo1= ' @p '

,

Prop2

=

V2

)

@Nofilt

F