第三章-词法分析

/** An interface that defines codes for Java source tokens
 *  returned from lexical analysis.
 */
public enum Token implements Formattable {
    EOF,
    ERROR,
    IDENTIFIER, // 如类名、包名、变量名、方法名等
    ABSTRACT("abstract"),
    ASSERT("assert"),
    BOOLEAN("boolean"),
    BREAK("break"),
    BYTE("byte"),
    CASE("case"),
    CATCH("catch"),
    CHAR("char"),
    CLASS("class"),
    CONST("const"),
    CONTINUE("continue"),
    DEFAULT("default"),
    DO("do"),
    DOUBLE("double"),
    ELSE("else"),
    ENUM("enum"),
    EXTENDS("extends"),
    FINAL("final"),
    FINALLY("finally"),
    FLOAT("float"),
    FOR("for"),
    GOTO("goto"),
    IF("if"),
    IMPLEMENTS("implements"),
    IMPORT("import"),
    INSTANCEOF("instanceof"),
    INT("int"),
    INTERFACE("interface"),
    LONG("long"),
    NATIVE("native"),
    NEW("new"),
    PACKAGE("package"),
    PRIVATE("private"),
    PROTECTED("protected"),
    PUBLIC("public"),
    RETURN("return"),
    SHORT("short"),
    STATIC("static"),
    STRICTFP("strictfp"),
    SUPER("super"),
    SWITCH("switch"),
    SYNCHRONIZED("synchronized"),
    THIS("this"),
    THROW("throw"),
    THROWS("throws"),
    TRANSIENT("transient"),
    TRY("try"),
    VOID("void"),
    VOLATILE("volatile"),
    WHILE("while"),
    INTLITERAL,
    LONGLITERAL,
    FLOATLITERAL,
    DOUBLELITERAL,
    CHARLITERAL,
    STRINGLITERAL,
    TRUE("true"),
    FALSE("false"),
    NULL("null"),
    LPAREN("("),
    RPAREN(")"),
    LBRACE("{"),
    RBRACE("}"),
    LBRACKET("["),
    RBRACKET("]"),
    SEMI(";"),
    COMMA(","),
    DOT("."),
    ELLIPSIS("..."),
    EQ("="),
    GT(">"),
    LT("<"),
    BANG("!"),
    TILDE("~"),
    QUES("?"),
    COLON(":"),
    EQEQ("=="),
    LTEQ("<="),
    GTEQ(">="),
    BANGEQ("!="),
    AMPAMP("&&"),
    BARBAR("||"),
    PLUSPLUS("++"),
    SUBSUB("--"),
    PLUS("+"),
    SUB("-"),
    STAR("*"),
    SLASH("/"),
    AMP("&"),
    BAR("|"),
    CARET("^"),
    PERCENT("%"),
    LTLT("<<"),
    GTGT(">>"),
    GTGTGT(">>>"),
    PLUSEQ("+="),
    SUBEQ("-="),
    STAREQ("*="),
    SLASHEQ("/="),
    AMPEQ("&="),
    BAREQ("|="),
    CARETEQ("^="),
    PERCENTEQ("%="),
    LTLTEQ("<<="),
    GTGTEQ(">>="),
    GTGTGTEQ(">>>="),
    MONKEYS_AT("@"),
    CUSTOM;
     
    // 省略相关的方法
}