问题描述
例如，使用以下代码段
/*
Checks if a target integer is present in the list of integers.
*/
public Boolean contains(Integer target,List<Integer> numbers) {
for(Integer number: numbers){
if(number.equals(target)){
return true;
}
}
return false;
}
元数据为：
Metadata = {
"comment": "Checks if a target integer is present in the list of integers.","identifier": "contains","parameters": "Integer target,List<Integer> numbers","return_statement": "Boolean false"
}
解决方法
该类是很久以前写的。实际上，它涉及大约四个不同的类-分布在名为JavaParserBridge的程序包中。它极大地简化了您要尝试做的事情。我剔除了所有不必要的内容，并将其煮沸到100行。花了大约一个小时...
我希望这一切都有道理。我通常会在代码中添加很多注释，但是有时在处理其他库时-并在Stack Overflow上发布-因为这实际上只是一个大的构造函数-我将为您提供Java Parser
要使用此类，只需将 Java类的源代码文件作为单个java.lang.String传递，名为getMethods(String)的方法将返回 Java Vector<Method>。返回的Vector的每个元素都有一个Method的实例，该实例应包含您在问题中要求的所有元信息。
重要提示：您可以从github页面上获取此软件包的 JAR 文件。您需要将 JAR 命名为：
javaparser-core-3.16.2.jar
import com.github.javaparser.StaticJavaParser;
import com.github.javaparser.ast.CompilationUnit;
import com.github.javaparser.ast.body.TypeDeclaration;
import com.github.javaparser.ast.body.MethodDeclaration;
import com.github.javaparser.ast.body.Parameter;
import com.github.javaparser.ast.type.ReferenceType;
import com.github.javaparser.ast.type.TypeParameter;
import com.github.javaparser.ast.Node;
import com.github.javaparser.ast.NodeList;
import com.github.javaparser.ast.Modifier; // Modifiers are the key-words such as "public,private,static,etc..."
import com.github.javaparser.printer.lexicalpreservation.LexicalPreservingPrinter;
import com.github.javaparser.printer.lexicalpreservation.PhantomNodeLogic;
import java.io.IOException;
import java.util.Vector;
public class Method
{
public final String name,signature,jdComment,body,returnType;
public final String[] modifiers,parameterNames,parameterTypes,exceptions;
private Method (MethodDeclaration md)
{
NodeList<Parameter> paramList = md.getParameters();
NodeList<ReferenceType> exceptionList = md.getThrownExceptions();
NodeList<Modifier> modifiersList = md.getModifiers();
this.name = md.getNameAsString();
this.signature = md.getDeclarationAsString();
this.jdComment = (md.hasJavaDocComment() ? md.getJavadocComment().get().toString() : null);
this.returnType = md.getType().toString();
this.modifiers = new String[modifiersList.size()];
this.parameterNames = new String[paramList.size()];
this.parameterTypes = new String[paramList.size()];
this.exceptions = new String[exceptionList.size()];
this.body = (md.getBody().isPresent()
? LexicalPreservingPrinter.print
(LexicalPreservingPrinter.setup(md.getBody().get()))
: null);
int i=0;
for (Modifier modifier : modifiersList) modifiers[i++] = modifier.toString();
i=0;
for (Parameter p : paramList)
{
parameterNames[i] = p.getName().toString();
parameterTypes[i] = p.getType().toString();
i++;
}
i=0;
for (ReferenceType r : exceptionList) this.exceptions[i++] = r.toString();
}
public static Vector<Method> getMethods(String sourceFileAsString) throws IOException
{
// This is the "Return Value" for this method (a Vector)
final Vector<Method> methods = new Vector<>();
// This asks Java Parser to parse the source code file
// The String-parameter 'sourceFileAsString' should have this
CompilationUnit cu = StaticJavaParser.parse(sourceFileAsString);
// This will "walk" all of the methods that were parsed by
// StaticJavaParser,and retrieve the method information.
// The method information is stored in a class simply called "Method"
cu.walk(MethodDeclaration.class,(MethodDeclaration md) -> methods.add(new Method(md)));
// There is one important thing to do: clear the cache
// Memory leaks shall occur if you do not.
PhantomNodeLogic.cleanUpCache();
// return the Vector<Method>
return methods;
}
}
您需要将此方法添加到上面的类中...我很少（如果有的话）为单个Stack Overflow问题添加多个答案。但是，由于使这变成了很多代码，所以没有使它变得过于复杂，而是将这种main方法发布为您问题的单独答案。
您需要在上面的类中包含此方法，它将正确处理您从我的网站下载的文件functions.json。正在处理的文件是一个名为functions.json的文件，它是包含方法列表及其数据库ID的文件。
ALSO：：请确保添加以下行：import java.util.regex.*，因为此方法使用了Java class Pattern和class Matcher
public static void main(String[] argv) throws IOException
{
// "321": "\tpublic int getPushesLowerbound() {\n\t\treturn pushesLowerbound;\n\t}\n",// If you have not used "Regular Expressions" before,you are just
// going to have to read about them. This "Regular Expression" parses your
// JSON "functions.json" file. It is a little complicated,but not too bad.
Pattern P1 = Pattern.compile("^\\s+\"(\\d+)\"\\:\\s+\"(.*?)\\\\n\",$");
BufferedReader br = new BufferedReader(new FileReader(new File("functions.json")));
String s = br.readLine();
// Any time you have a "Constructor" instead of a method,you should
// use some other method in `StaticJavaParser` to deal with it.
// for now,I am just going to keep a "Fail List" instead..
int failCount = 0;
Vector<String> failIDs = new Vector<>();
while (! (s = br.readLine()).equals("}"))
{
// Parse the JSON using a Regular Expression. It is just easier to do it this way
// You have a VERY BASIC json file.
Matcher m = P1.matcher(s);
// I do not think any of the String's will fail the regular expression matcher.
// Just in case,continue if the Regular Expression Match Failed.
if (! m.find()) { System.out.print("."); continue; }
// The ID is the first JSON element matched by the regular expression
String id = m.group(1);
// The source code is the second JSON element matched by the regular-expression
// NOTE: Your source-code is not perfect... It has "escape sequences",so these sequennces
// have to be "unescaped"
// ALSO: this is not the most efficient way to "un-escape" an escape-sequence,but I would
// have to include an external library to do it the right way,so I'm going to leave
// this version here for your to think about.
String src = m.group(2)
.replace("\\\\","" + ((char) 55555))
.replace("\\n","\n")
.replace("\\t","\t")
.replace("\\\"","\"")
.replace("" + ((char) 55555),"\\");
// Java Parser has a method EXPLICITLY FOR parsing method Declarations.
// Your "functions.json" file has a list of method-declarations.
MethodDeclaration md = null;
// I found one that failed - it was a constructor..
try
{ md = StaticJavaParser.parseMethodDeclaration(src); }
catch (Exception e)
{ System.out.println(src); e.printStackTrace(); failCount++; continue; }
Method method = new Method(md);
System.out.print(
"ID: " + id + '\n' +
"Name: " + method.name + '\n' +
"Return Type: " + method.returnType + '\n' +
"Parameters: "
);
for (int i=0; i < method.parameterNames.length; i++)
System.out.print(method.parameterNames[i] + '(' + method.parameterTypes[i] + ") ");
System.out.println("\n");
PhantomNodeLogic.cleanUpCache();
}
System.out.print(
"Fail Count: " + failCount + "\n" +
"Failed ID's: "
);
for (String failID : failIDs) System.out.print(failID + " ");
System.out.println();
}
以上方法将产生这种类型的输出。既然您拥有一百万种方法，那么它将运行一段时间。
注意：：并非该列表中的每个方法都是有效方法。如果有构造函数而不是方法，则需要将其解析为构造函数。对于 JavaParser 无法解析的方法，有一个“失败列表”-我将作为练习来留给您，以帮助您弄清楚如何处理Constructors （未通过名为StaticJavaParser的{{1}}方法进行解析
注意：：此操作将运行 很长一段时间 -我仅发布了此{的非常小的子集{ {1}}方法...
parseMethodDeclaration 重要提示 ：（再次）任何时候，您的任何数据库功能都是 构造函数 而不是 方法 在main(String[] argv)中使用的 JavaParser 方法将引发异常。
参见此处：这是一个构造函数：
ID: 32808641
Name: addUnboundTypePropertyDescriptor
Return Type: void
Parameters: object(Object)
ID: 32808649
Name: addNamePropertyDescriptor
Return Type: void
Parameters: object(Object)
ID: 32808650
Name: addInputParameterPropertyDescriptor
Return Type: void
Parameters: object(Object)
ID: 32808651
Name: addQualifiedNamePropertyDescriptor
Return Type: void
Parameters: object(Object)
ID: 32808652
Name: addOutputParameterPropertyDescriptor
Return Type: void
Parameters: object(Object)
ID: 32808656
Name: addReturnParameterPropertyDescriptor
Return Type: void
Parameters: object(Object)
ID: 32808658
Name: addSignatureParameterPropertyDescriptor
Return Type: void
Parameters: object(Object)
ID: 32808659
Name: getLabelProvider
Return Type: IItemLabelProvider
Parameters: namedElement(NamedElement)
ID: 32808661
Name: getLabel
Return Type: String
Parameters: namedElement(NamedElement)
ID: 32808677
Name: addBodyPropertyDescriptor
Return Type: void
Parameters: object(Object)
ID: 32808678
Name: addLanguagePropertyDescriptor
Return Type: void
Parameters: object(Object)
ID: 32808696
Name: addKindPropertyDescriptor
Return Type: void
Parameters: object(Object)
ID: 32808707
Name: addStaticPropertyDescriptor
Return Type: void
Parameters: object(Object)
ID: 32808708
Name: addKindPropertyDescriptor
Return Type: void
Parameters: object(Object)
ID: 32808709
Name: addSemanticsPropertyDescriptor
Return Type: void
Parameters: object(Object)
ID: 32808711
Name: addConstrainedElementPropertyDescriptor
Return Type: void
Parameters: object(Object)
ID: 32808713
Name: addDefinedFeaturePropertyDescriptor
Return Type: void
Parameters: object(Object)
ID: 32808727
Name: addNestingNamespacePropertyDescriptor
Return Type: void
Parameters: object(Object)
ID: 32808741
Name: addKindPropertyDescriptor
Return Type: void
Parameters: object(Object)
ID: 32808749
Name: addSuperTypePropertyDescriptor
Return Type: void
Parameters: object(Object)
ID: 32814359
Name: getResource
Return Type: ResourceBundle
Parameters: name(String) language(String)
ID: 32814360
Name: store
Return Type: void
Parameters: resource(ResourceBundle) name(String) language(String)
ID: 32814364
Name: getString
Return Type: String
Parameters: key(String) resourceName(String) language(String)
ID: 32814400
Name: getGlobalCompletionRate
Return Type: double
Parameters:
ID: 32814409
Name: setCurrentSubTask
Return Type: void
Parameters: subTask(TaskMonitor) subTaskShare(double)
ID: 32814429
Name: enforceCompletion
Return Type: void
Parameters:
ID: 32814431
Name: getCurrentActiveSubTask
Return Type: TaskMonitor
Parameters:
ID: 32814469
Name: checkTaskState
Return Type: void
Parameters:
ID: 32814619
Name: getReportAsText
Return Type: String
Parameters: report(ProcessReport)
ID: 32815305
Name: showRecoveryResultWindow
Return Type: void
Parameters: context(ProcessContext)
ID: 32815353
Name: validateStructure
Return Type: void
Parameters:
ID: 32815413
Name: buildArchive
Return Type: void
Parameters: context(ProcessContext)
ID: 32815445
Name: checkArchiveCompatibility
Return Type: boolean
Parameters: archive(File)
ID: 32815446
Name: checkStupidConfigurations
Return Type: boolean
Parameters:
ID: 32815472
Name: getDescription
Return Type: String
Parameters:
ID: 32815501
Name: getDataDirectory
Return Type: File
Parameters: archive(File)
我发布的代码在遇到此消息时会打印此消息：
class StaticJavaParser