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java AST JCTree简要分析

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发布于 2019/08/22 20:54
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JCTree简要分析

[toc]

JCAnnotatedType

被注解的泛型:(注解的Target为ElementType.TYPE_USE时可注解泛型)

public static class A<T extends @Reality String> { } 
  • JCAnnotatedType @Reality() String
  • annotations (List<JCTree.JCAnnotation>) [0] = (JCAnnotation) @Reality()
  • underlyingType (JCExpression) = (JCIdent) String
protected JCAnnotatedType(List<JCTree.JCAnnotation> var1, JCTree.JCExpression var2) {
    Assert.check(var1 != null && var1.nonEmpty()); this.annotations = var1; this.underlyingType = var2; } 

JCAnnotation

注解:@annotationType(args) 例子:@Reality(callSuper = false)

  • JCAnnotation @Reality(callSuper = false)
  • annotationType (JCTree) = (JCIdent) Reality
  • args (List<JCExpression>) = callSuper = false
  • attribute (Compound) = @com.juno.annotations.Reality(callSuper=false)
protected JCAnnotation(JCTree.Tag var1, JCTree var2, List<JCTree.JCExpression> var3) {
    this.tag = var1; this.annotationType = var2; this.args = var3; } 

JCArrayAccess

数组访问:a[0] = "123"

  • index (JCExpression) = 0 (JCLiteral)
  • indexed (JCExpression) = a (JCIdent)
protected JCArrayAccess(JCTree.JCExpression var1, JCTree.JCExpression var2) {
    this.indexed = var1; this.index = var2; } 

JCArrayTypeTree

数组类型:String[] a = new String[2] 中表达式的右边:

  • elemtype (JCExpression) = String (JCIdent)

二维数组:String[][] a = new String[1][2]解析为:

  • JCArrayTypeTree String[]
  • JCIdent String
protected JCArrayTypeTree(JCTree.JCExpression var1) {
    this.elemtype = var1; } 

JCAssert

assert断言:assert cond : detail

protected JCAssert(JCTree.JCExpression var1, JCTree.JCExpression var2) {
    this.cond = var1; this.detail = var2; } 

JCAssign

赋值:lhs = rhs 例如 i = 1

protected JCAssign(JCTree.JCExpression var1, JCTree.JCExpression var2) {
    this.lhs = var1; //左表达式 this.rhs = var2; //右表达式 } 

JCAssignOp

赋值:lhs opcode rhs 例如 i += 1

protected JCAssignOp(JCTree.Tag var1, JCTree var2, JCTree var3, Symbol var4) {
    this.opcode = var1; this.lhs = (JCTree.JCExpression)var2; this.rhs = (JCTree.JCExpression)var3; this.operator = var4; } 

赋值符号opcode的可取值:

/** Assignment operators, of type Assignop.
 */
BITOR_ASG(BITOR),                // |=
BITXOR_ASG(BITXOR),              // ^=
BITAND_ASG(BITAND),              // &=

SL_ASG(SL),                      // <<= SR_ASG(SR), // >>= USR_ASG(USR), // >>>= PLUS_ASG(PLUS), // += MINUS_ASG(MINUS), // -= MUL_ASG(MUL), // *= DIV_ASG(DIV), // /= MOD_ASG(MOD), // %= 

JCBinary

将语句分为二叉结构,例如double i = d + i * f 中第一个JCBinary为:

  • lhs = d
  • rhs = i * f
  • operator = null
  • opcode = PLUS

第二个JCBinary为:

  • lhs = i
  • rhs = f
  • operator = null
  • opcode = MUL
protected JCBinary(JCTree.Tag var1, JCTree.JCExpression var2, JCTree.JCExpression var3, Symbol var4) {
    this.opcode = var1; this.lhs = var2; this.rhs = var3; this.operator = var4; } 

二元运算符opcode的可取值:

/** Binary operators, of type Binary.
 */
OR,                              // ||
AND,                             // &&
BITOR,                           // |
BITXOR,                          // ^ BITAND, // & EQ, // == NE, // != LT, // < GT, // > LE, // <= GE, // >= SL, // << SR, // >> USR, // >>> PLUS, // + MINUS, // - MUL, // * DIV, // / MOD, // % 

JCBlock

语句块:{stats} 或 static{stats}(flags = 8L时)

protected JCBlock(long var1, List<JCTree.JCStatement> var3) { this.stats = var3; this.flags = var1; } 

JCBreak

break语句:break:label

  • label 为标签名
  • target 为跳转目标
protected JCBreak(Name var1, JCTree var2) {
    this.label = var1; this.target = var2; } 

JCCase

case语句:case pat : stats

protected JCCase(JCTree.JCExpression var1, List<JCTree.JCStatement> var2) {
    this.pat = var1; this.stats = var2; } 

JCCatch

catch捕捉异常:catch(param) body

  • param 定义异常变量 Exception e
  • body 代码块
protected JCCatch(JCTree.JCVariableDecl var1, JCTree.JCBlock var2) {
    this.param = var1; this.body = var2; } 

JCClassDecl

类的定义:

例子:

@Reality
public class MainActivity extends AppCompatActivity { private int kk = 1; static { kk = 2; } @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); } } 
  • mods (JCModifiers) = public
  • name (Name) = (NameImpl) MainActivity
  • extending (JCExpression) = (JCIdent) AppCompatActivity
  • implementing (JCExpression) 实现的接口
  • defs (List<JCTree>) :
  • defs(1) : JCMethodDecl
    public <init>() {
        super();
    }
    
  • defs(2) : JCBlock
    static {
        kk = 2;
    }
    
  • defs(3) : JCVariableDecl
    private int kk = 1
    
  • defs(4) : JCMethodDecl
    @Override()
    protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); TextView textView = findViewById(R.id.text); Random random = new Random(); } 
  • sym (ClassSymbol) = com.juno.utils.MainActivity
protected JCClassDecl(JCTree.JCModifiers var1, Name var2, List<JCTree.JCTypeParameter> var3, JCTree.JCExpression var4, List<JCTree.JCExpression> var5, List<JCTree> var6, ClassSymbol var7) {
    this.mods = var1; this.name = var2; this.typarams = var3; this.extending = var4; this.implementing = var5; this.defs = var6; this.sym = var7; } 

JCCompilationUnit

/**
 * Everything in one source file is kept in a TopLevel structure.
 * @param pid The tree representing the package clause. 
 * @param sourcefile The source file name.
 * @param defs All definitions in this file (ClassDef,Import,and Ski
 * @param packge The package it belongs to. * @param namedImportScope A scope for all named imports. * @param starImportScope A scope for all import-on-demands. * @param linelMap Line starting positions,defined only if option-g is set. * @param docComments A hashtable that stores all documentation comments indexed by the tree nodes they refer to.defined only if option-s is set. * @param endPositions A hashtable that stores ending positions of source ranges indexed by the tree nodes they belong to. Defined only if option-Xjcov is set. */ public static class JCCompilationUnit extends JCTree implements CompilationUnitTre{ public List<JCAnnotation>packageAnnotations: public JCExpression pid: public List<JCTree>defs: public JavaFileObject sourcefile: public Package Symbol packge: public ImportScope namedImportScope: public StarImportScope starImportScope: public long flags: public Position.LinelMap linelMap=null: public Map<JCTree,String>docComments=null: public Map<JCTree,Integer>endPositions=null: protected JCCompilationUnit(List<JCAnnotation>packageAnnotations, JCExpression pid, List<JCTree>defs, JavaFileObject sourcefile, Pack ageSymbol packge, ImportScope namedImportScope, Star ImportScope starImportScope){ this.packageAnnotations =packageAnnotations: this.pid=pid: this.defs=defs: this.sourcefile=sourcefile: this.packge=packge: this.namedImportScope=namedImportScope: this.starImportScope=starImportScope: } } 

JCConditional

三目运算符:cond ? truepart : falsepart 例如 a ? 1 : 3

protected JCConditional(JCTree.JCExpression var1, JCTree.JCExpression var2, JCTree.JCExpression var3) {
    this.cond = var1; this.truepart = var2; this.falsepart = var3; } 

JCContinue

continue跳过一次循环,与break相似:continue label

protected JCContinue(Name var1, JCTree var2) {
    this.label = var1; this.target = var2; } 

JCDoWhileLoop

do-while循环:do{body}while(cond)

protected JCDoWhileLoop(JCTree.JCStatement var1, JCTree.JCExpression var2) {
    this.body = var1; this.cond = var2; } 

JCEnhancedForLoop

增强循环:for(var : expr) body

例如:

for (String s : list) {
    print(s);
}
  • JCVariableDecl String s 定义字符串变量s
  • JCIdent list 遍历的容器
  • JCBlock { print(s); } 遍历块
protected JCEnhancedForLoop(JCTree.JCVariableDecl var1, JCTree.JCExpression var2, JCTree.JCStatement var3) {
    this.var = var1; this.expr = var2; this.body = var3; } 

JCErroneous

Error trees

JCExpression

表达式,赋值、调用方法等都算一个表达式,凡是继承JCExpression都算一个表达式

JCExpressionStatement

内部封装了JCExpression,实际上还是个表达式

protected JCExpressionStatement(JCTree.JCExpression var1) {
    this.expr = var1; } 

JCFieldAccess

访问父类、其他类的方法、变量时:super.onCreate()

  • selected (JCIdent) = super
  • name (NameImpl) = onCreate
protected JCFieldAccess(JCTree.JCExpression var1, Name var2, Symbol var3) {
    this.selected = var1; this.name = var2; this.sym = var3; } 

JCForloop

for循环:

  • for (init; cond; step) {body}(body为JCBlock
  • for (init; cond; step) body(body为JCExpressionStatement
protected JCForLoop(List<JCTree.JCStatement> var1, JCTree.JCExpression var2, List<JCTree.JCExpressionStatement> var3, JCTree.JCStatement var4) {
    this.init = var1; this.cond = var2; this.step = var3; this.body = var4; } 

JCFunctionalExpression

函数式表达式:lambda(JCLambda)和method reference(JCMemberReference)继承于JCFunctionalExpression

JCIdent

出现在表达式中的变量名、调用的方法名以及类名等,例子如下(按顺序):

  • Reality 类(注解)
  • AppCompatActivity 类
  • String 类
  • Override 类
  • Bundle 类
  • super super和this都是一个JcIdent
  • savedInstanceState 调用变量的名字
  • setContentView 方法
  • R 类
  • textView 调用变量的名字
  • findViewById 方法
  • R类
@Reality //JCIdent Reality ClassSymbol com.juno.annotations.Reality
//JCIdent AppCompatActivity ClassSymbol android.support.v7.app.AppCompatActivity
public class MainActivity extends AppCompatActivity { //JCIdent String ClassSymbol java.lang.String private static final String TAG = "MainActivity"; private int kk = 1; @Override //JCIdent Override ClassSymbol java.lang.Override //JCIdent Bundle ClassSymbol android.os.Bundle protected void onCreate(Bundle savedInstanceState) { //JCIdent super //JCIdent savedInstanceState super.onCreate(savedInstanceState); //JCIdent setContentView //JCIdent R setContentView(R.layout.activity_main); TextView textView; //JCIdent textView //JCIdent findViewById //JCIdent R textView = findViewById(R.id.text); int i = 0; int j = 1; //JCIdent i //JCIdent j i = j * 3 + 2; //JCIdent this this.kk = 0; } } 

其中TextView textView;这一句是变量定义语句(JCVariableDecl),该语句的vartype属性实际上也是个JCIdent:

  • JCVariableDecl TextView textView
  • name (Name) = textView (NameImpl)
  • vartype (JCExpression) = TextView (JCIdent)

JCIf

if判断语句:if(condition) {thenpart} else {elsepart}

protected JCIf(JCTree.JCExpression var1, JCTree.JCStatement var2, JCTree.JCStatement var3) {
    this.cond = var1; this.thenpart = var2; this.elsepart = var3; } 

JCImport

import语句:

  • import qulid
  • static (if staticImport) import qulid
protected JCImport(JCTree var1, boolean var2) { this.qualid = var1; this.staticImport = var2; } 

JCinstanceOf

instanceof语句:expr instanceof clazz,例如textView instanceof View:

  • JCInstanceOf textView instanceof View
  • clazz (JCTree) = (JCIdent) View
  • expr (JCExpression) = (JCIdent) textView
protected JCInstanceOf(JCTree.JCExpression var1, JCTree var2) {
    this.expr = var1; this.clazz = var2; } 

JCLabeledStatement

带有标签的语句:label : body

protected JCLabeledStatement(Name var1, JCTree.JCStatement var2) {
    this.label = var1; this.body = var2; } 

JCLambda

lambda表达式:此处表达式主体只有一句表达式

textView.setOnClickListener(v -> v.setVisibility(View.INVISIBLE));
  • JCLambda (v)->v.setVisibility(View.INVISIBLE) (表达式整体)
  • params (List<JCTree.JCVariableDecl>) = (List) /*missing*/ v (参数定义列表)
  • body (JCTree) = (JCMethodInvocation) v.setVisibility(View.INVISIBLE) (主体)
  • canCompleteNormally (Boolean) = true (未知)
  • paramKind (ParameterKind) = IMPLICIT (参数类型隐形/明确)
  • getBodyKind() (BodyKind) = EXPRESSION (主体是表达式还是块)

当主体变为语句块时:

textView.setOnClickListener(v -> {
    v.setVisibility(View.VISIBLE);
});
  • body (JCTree) = (JCBlock) {v.setVisibility(View.VISIBLE);}
  • getBodyKind() (BodyKind) = STATEMENT

当参数v指明类型为View时:

textView.setOnClickListener((View v) -> v.setVisibility(View.INVISIBLE));
  • paramKind (ParameterKind) = IMPLICIT (参数类型明确)

JCLiteral

表示常量:int a = 1

  • typetag (TypeTag) = INT
  • value (Object) = (Integer) 1
protected JCLiteral(TypeTag var1, Object var2) {
    this.typetag = var1; this.value = var2; } 

typetag的可选值有:

INT : int
LONG : long
FLOAT : float
DOUBLE : double
CHAR : char CLASS : String BOT : null 

JCMemberReference

lambda表达式中的方法引用:expr::name

例子:new B<String>("123").setObjectUtil(ObjectUtil::new);

  • JCMemberReference ObjectUtil::new
  • mode (ReferenceMode) = NEW
  • name (Name) = (NameImpl) <init>
  • expr (JCExpression) = (JCIdent) ObjectUtil

例子:new B<String>("123").setObjectUtil(this::util);

  • JCMemberReference this::util
  • mode (ReferenceMode) = INVOKE
  • name (Name) = (NameImpl) util
  • expr (JCExpression) = (JCIdent) this
protected JCMemberReference(ReferenceMode var1, Name var2, JCTree.JCExpression var3, List<JCTree.JCExpression> var4) {
    this.mode = var1; this.name = var2; this.expr = var3; this.typeargs = var4; } 

JCMethodDecl

方法的定义:

例子:

@Reality
private static <T extends String> int print(@NonNull final String s) throws RuntimeException { Log.e(TAG, s); return 1; } 
  • mods (JCModifiers) = @Reality() private static
  • name (Name) = (NameImpl) print
  • restype (JCExpression) = (JCPrimitiveTypeTree) int
  • typarams (JCTypeParameter) = T extends String
  • recvparam = null
  • params (List<JCVariableDecl>) [0] = @NonNull() final String s
  • thrown (JCExpression) = (JCIdent) RuntimeException
  • body (JCBlock) = {
    Log.e(TAG, s);
    return 1;
    }
  • defaultVaule (JCExpression) = null
  • sym (MethodSymbol) = <T>print(java.lang.String)

例子:

@Reality
@interface B {
    int value() default 1; } 
  • name (Name) = (NameImpl) value
  • restype (JCExpression) = (JCPrimitiveTypeTree) int
  • typarams (JCTypeParameter) 泛型列表为空
  • recvparam = null
  • params (List<JCVariableDecl>) 参数定义为空
  • thrown (JCExpression) 抛出列表为空
  • body (JCBlock) 方法体为空
  • defaultVaule (JCExpression) = (JCLiteral) 1
  • sym (MethodSymbol) = value()
protected JCMethodDecl(JCTree.JCModifiers var1, Name var2, JCTree.JCExpression var3, List<JCTree.JCTypeParameter> var4, JCTree.JCVariableDecl var5, List<JCTree.JCVariableDecl> var6, List<JCTree.JCExpression> var7, JCTree.JCBlock var8, JCTree.JCExpression var9, MethodSymbol var10) {
    this.mods = var1; this.name = var2; this.restype = var3; this.typarams = var4; this.params = var6; this.recvparam = var5; this.thrown = var7; this.body = var8; this.defaultValue = var9; this.sym = var10; } 

JCMethodinvocation

方法执行语句: meth(args)

例子:notNull(before)

  • meth (JCExpression) = (JCIdent) notNull
  • args (List<JCExpression>) = (JCIdent) before

例子:proxy.invoke(target, method, args)

  • meth (JCExpression) = (JCFieldAccess) proxy.invoke
  • args (List<JCExpression>) = (JCIdent) target, method, args
protected JCMethodInvocation(List<JCTree.JCExpression> var1, JCTree.JCExpression var2, List<JCTree.JCExpression> var3) {
    this.typeargs = var1 == null ? List.nil() : var1; this.meth = var2; this.args = var3; } 

JCModifiers

类、变量、方法等的修饰符和注解:例如:

@Reality private static final String TAG = "MainActivity"; 
  • flags (long) = 26L (2L | 8L | 16L)
  • annotations (List<JCTree.JCAnnotation>) = @Reality()
protected JCModifiers(long var1, List<JCTree.JCAnnotation> var3) { this.flags = var1; this.annotations = var3; } 

flags的可取值:

1L : public
2L : private
4L : protected 8L : static 16L : final 32L : synchronized 64L : volatile 128L : transient 256L : native 1024L : abstract 2048L : strictfp 8589934592L : default 

方法默认flags不为default,而是0L

JCNewArray

new数组:

例子:String[] s = new String[]{"123","456"};

  • JCNewArray new String[]{"123", "456"}
  • elemtype (JCExpression) = (JCIdent) String
  • dims (List<JCTree.JCExpression>) 空
  • elems (List<JCTree.JCExpression>) [0] = (JCLiteral) "123"
  • elems (List<JCTree.JCExpression>) [1] = (JCLiteral) "456"

例子:B<String>[][] b = new B[3][4];

  • JCNewArray new B[3][4]
  • elemtype (JCExpression) = (JCIdent) B
  • dims (List<JCTree.JCExpression>) [0] = (JCLiteral) 3
  • dims (List<JCTree.JCExpression>) [1] = (JCLiteral) 4
  • elems (List<JCTree.JCExpression>) 空
protected JCNewArray(JCTree.JCExpression var1, List<JCTree.JCExpression> var2, List<JCTree.JCExpression> var3) {
    this.elemtype = var1; this.dims = var2; this.annotations = List.nil(); this.dimAnnotations = List.nil(); this.elems = var3; } 

JCNewClass

new一个对象:

例子:new B<String>("123")

  • JCNewClass new B<String>("123")
  • clazz (JCExpression) = (JCTypeApply) B<String>
  • args (List<JCTree.JCExpression>) [0] = (JCLiteral) "123"
protected JCNewClass(JCTree.JCExpression var1, List<JCTree.JCExpression> var2, JCTree.JCExpression var3, List<JCTree.JCExpression> var4, JCTree.JCClassDecl var5) {
    this.encl = var1; this.typeargs = var2 == null ? List.nil() : var2; this.clazz = var3; this.args = var4; this.def = var5; } 

JCParens

括号:(expr) 存在于if、计算式、synchronized中

protected JCParens(JCTree.JCExpression var1) {
    this.expr = var1; } 

JCPrimitiveTypeTree

基本类型:

基本类型的赋值:int i = 0 :

  • typetag = INT

方法的返回值:void print(String s) {Log.e(TAG, s);}

  • typetag = VOID
protected JCPrimitiveTypeTree(TypeTag var1) {
    this.typetag = var1; } 

typetag可选值:

INT : int
LONG : long
FLOAT : float
DOUBLE : double
DOOLEAN : boolean CHAR : char BYTE : byte short : short VOID : void 

JCReturn

return语句:return expr

protected JCReturn(JCTree.JCExpression var1) {
    this.expr = var1; } 

JCSkip

空操作,即一个无效的分号 ";"

JCStatement

声明:凡是继承JCStatement都是一个声明,在JCBlock中拿到的都是JCStatement,想在JCBlock中拿到JCExpression就用JCExpressionStatement

JCSWitch

switch语句:switch(selector) {cases}

protected JCSwitch(JCTree.JCExpression var1, List<JCTree.JCCase> var2) {
    this.selector = var1; this.cases = var2; } 

JCSynchronized

synchronized同步锁:synchronized(lock){block}

protected JCSynchronized(JCTree.JCExpression var1, JCTree.JCBlock var2) {
    this.lock = var1; this.body = var2; } 

JCThrow

抛出异常:throw expr

protected JCThrow(JCTree.JCExpression var1) {
    this.expr = var1; } 

JCTry

try块:try body catchers finally finalizer

protected JCTry(List<JCTree> var1, JCTree.JCBlock var2, List<JCTree.JCCatch> var3, JCTree.JCBlock var4) {
    this.body = var2; this.catchers = var3; this.finalizer = var4; this.resources = var1; } 

resources不知道是什么

JCTypeApply

泛型参数:List<String> list = new ArrayList<>()

对于List<String> list:

  • clazz (JCExpression) = (JCIdent) List
  • arguments (List<JCTree.JCExpression>) [0] = (JCIdent) String

对于new ArrayList<>():

  • clazz (JCExpression) = (JCIdent) ArrayList
  • arguments (List<JCTree.JCExpression>) = empty
protected JCTypeApply(JCTree.JCExpression var1, List<JCTree.JCExpression> var2) {
    this.clazz = var1; this.arguments = var2; } 

JCTypeCast

类型转换:(clazz)expr

例子:View textView = ((TextView) findViewById(R.id.text));

  • JCTypeCast (TextView)findViewById(R.id.text)
  • clazz (JCTree) = (JCIdent) TextView
  • expr (JCExpression) = (JCMethodInvocation) findViewById(R.id.text)

例子:TextView t = (TextView) textView;

  • JCTypeCast (TextView)textView
  • clazz (JCTree) = (JCIdent) TextView
  • expr (JCExpression) = (JCIdent) textView
protected JCTypeCast(JCTree var1, JCTree.JCExpression var2) {
    this.clazz = var1; this.expr = var2; } 

JCTypelntersection

unknown

泛型交叉:

public static class A<T extends String & Runnable> { } 
protected JCTypeIntersection(List<JCTree.JCExpression> var1) {
    this.bounds = var1; } 

JCTypeParameter

类的泛型定义:class<annotations name bounds>

  • JCTypeParameter @Anno() T extends View
  • name (Name) = (NameImpl) T
  • bounds (List<JCTree.JCExpression>) [0] = (JCIdent) View
    JCAnnotation @MainActivity.A()
protected JCTypeParameter(Name var1, List<JCTree.JCExpression> var2, List<JCTree.JCAnnotation> var3) {
    this.name = var1; this.bounds = var2; this.annotations = var3; } 

JCTypeUnion

catch块中异常的或定义:T1 | T2 | ... Tn

try{
    ...
}catch (ClassCastException | ArrayIndexOutOfBoundsException e){
    ...
}
  • JCTypeUnion ClassCastException | ArrayIndexOutOfBoundsException
  • alternatives (List<JCTree.JCExpression>) [0] = (JCIdent) ClassCastException
  • alternatives (List<JCTree.JCExpression>) [1] = (JCIdent) ArrayIndexOutOfBoundsException
protected JCTypeUnion(List<JCTree.JCExpression> var1) {
    this.alternatives = var1; } 

JCUnary

一元运算语句:i++中

  • opcode = POSTINC
  • arg = i (实际是JCIdent类型)
protected JCUnary(JCTree.Tag var1, JCTree.JCExpression var2) {
    this.opcode = var1; this.arg = var2; } 
/** Unary operators, of type Unary.
 */
POS,                             // +
NEG,                             // -
NOT,                             // !
COMPL,                           // ~ PREINC, // ++ _ PREDEC, // -- _ POSTINC, // _ ++ POSTDEC, // _ -- 

JCVariableDecl

定义变量: mods vartype name = init

例子:final TextView textView = findViewById(R.id.text);

  • JCVariableDecl final TextView textView = findViewById(R.id.text)
  • mods (JCModifiers) = final
  • name (Name) = (NameImpl) textView
  • vartype (JCExpression) = (JCIdent) TextView
  • init (JCExpression) = (JCMethodInvocation) findViewById(R.id.text)

例子:double i = 1 + 2 * 3;

  • JCVariableDecl double i = 1 + 2 * 3
  • name (Name) = (NameImpl) i
  • vartype (JCExpression) = (JCPrimitiveTypeTree) double
  • init (JCExpression) = (JCBinary) 1 + 2 * 3

例子:int k = cond ? 0 : 1;

  • JCVariableDecl int k = cond ? 0 : 1
  • init (JCExpression) = (JCConditional) cond ? 0 : 1
protected JCVariableDecl(JCTree.JCModifiers var1, Name var2, JCTree.JCExpression var3, JCTree.JCExpression var4, VarSymbol var5) {
    this.mods = var1; this.name = var2; this.vartype = var3; this.init = var4; this.sym = var5; } 

JCWhileLoop

while循环:while(cond){body}

为什么body不是Statement List或Block?

protected JCWhileLoop(JCTree.JCExpression var1, JCTree.JCStatement var2) {
    this.cond = var1; this.body = var2; } 

JCWildcard

泛型中的"?"通配符:Class<? super String> c;

  • JCWildcard ? super String
  • kind (TypeBoundKind) = ? super
  • inner (JCTree) = (JCIdent) String
protected JCWildcard(JCTree.TypeBoundKind var1, JCTree var2) {
    var1.getClass();
    this.kind = var1; this.inner = var2; } 

 

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