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#Java - Code Snippets for '#Class' - 67 code snippet(s) found

 Sample 1. Example of Factory Class

public final class EmployeeFactory {

private Employee svEmp;

public EmployeeFactory(String type){
if( type.equals("Manager")){
svEmp = new Manager();
} else if(type.equals("Developer")){
svEmp = new Developer();
} else if(type.equals("QA")){
svEmp = new QA();
}
}

public Employee getFactoryProduct() {
return svEmp;
}

}

   Like      Feedback     factory design pattern  factory class  final class  composition


 Sample 2. Singleton Class ( using private constructor , object initialization using static method, doubly checked , thread safe, synchronized , volatile reference )

class Singleton {
private static volatile Singleton instance = null;
private Singleton(){}
public static Singleton getInstance() {
if (instance == null) {
synchronized(Singleton.class) {
if (instance== null)
instance = new Singleton();
}
}
return instance;
}
}

   Like      Feedback     singleton   singleton class   volatile   private constructor    object initialization using static method   doubly checked    thread safe   synchronized block using class level lock   synchronized   synchronized block   class level lock  object initialization using getInstance


 Sample 3. Class Nested within Interface / Static Inner class within Interface

public interface SampleInterface {
   public int sampleMethod(List sampleList);

   static class Impl implements SampleInterface {

      @Override
      public int sampleMethod(List sampleList) {
         return 0;
      }
   }
}

   Like      Feedback     nested classes  nested class  inner class  inner classes  static inner class  static inner class within interface  @override


 Sample 4. Code Sample / Example / Snippet of org.apache.spark.ml.classification.LogisticRegressionModel

  public static void main(String[] args) {

SparkConf conf = new SparkConf().setAppName("JavaLogisticRegressionWithElasticNetExample");

JavaSparkContext jsc = new JavaSparkContext(conf);

SQLContext sqlContext = new SQLContext(jsc);



DataFrame training = sqlContext.read().format("libsvm")

.load("data/mllib/sample_libsvm_data.txt");



LogisticRegression lr = new LogisticRegression()

.setMaxIter(10)

.setRegParam(0.3)

.setElasticNetParam(0.8);



LogisticRegressionModel lrModel = lr.fit(training);



System.out.println("Coefficients: "

+ lrModel.coefficients() + " Intercept: " + lrModel.intercept());



jsc.stop();

}


   Like      Feedback      org.apache.spark.ml.classification.LogisticRegressionModel


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 Sample 5. Declaring Abstract Class

public abstract class TestClass {
public static void main(String[] args){
}
}

   Like      Feedback     abstract classes  main method declaration  main method


 Sample 6. Declaring static final ( constant ) variables.

public abstract class TestClass {

   protected static final String TEST_STRING = "test";

   public static void main(String[] args){
   }
}

   Like      Feedback     static final variables   constant variables


 Sample 7. Interface Default Methods ( Base Class Definition has precedence over Interface Default Method if both are being extended and implemented and have common method definition )

HelloJava8Base 

public class HelloJava8Base {
public void defaultMethod() {
System.out.println("Default Method Base Class Implementation");
}
}

DefaultMethodInterface

public interface DefaultMethodInterface {
default public void defaultMethod() {
System.out.println("Default Method Interface Implementation");
}
}

HelloJava8

public class HelloJava8 extends HelloJava8Base implements DefaultMethodInterface,DefaultMethodInterface2 {
public static void main(String[] args){
DefaultMethodInterface dmi = new HelloJava8();
dmi.defaultMethod(); // Prints "Default Method Base Class Implementation"
}
}

   Like      Feedback     interface default methods  java 8  interfaces


 Sample 8. Class bean with getter , setter and constructor

public class Employee {
public String name;
public int age;
public int salary;

Employee(String name, int age, int salary) {
this.name = name;
this.age = age;
this.salary = salary;
}

public String getName() {
return name;
}

public void setName(String name) {
this.name = name;
}

public int getAge() {
return age;
}

public void setAge(int age) {
this.age = age;
}

public int getSalary() {
return salary;
}

public void setSalary(int salary) {
this.salary = salary;
}
}

   Like      Feedback     bean   pojo   plain java objects   getters   setters   getters nd setters   classes   class   constructor   parameterized constructor  this keyword


 Sample 9. Load Properties using Property Class

private static Properties props = null;
   
private static void loadProperties(){
   try {
      if(props == null || props1 == null || props2 == null){
         props = new Properties();
         props.load(new FileInputStream(Constants.PROP_BASE_DIR + Constants.EMPLOYEE_REPORTING_PROP));
      } catch (FileNotFoundException e) {
         // TODO Auto-generated catch block
         e.printStackTrace();
      } catch (IOException e) {
         // TODO Auto-generated catch block
         e.printStackTrace();
      }

   }
}

   Like      Feedback     property class  properties  FileInputStream  file handling


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 Sample 10. Method to check if the the file exists and not a directory

public static boolean isOleFile(File file)
{
   if ((file == null) || (!file.exists()) || (file.isDirectory())) {
      return false;
   }

   return true;
}

   Like      Feedback     file handling  check if file exists  File class  check if file is a directory  file.isDirectory  file.exists


 Sample 11. Code Sample / Example / Snippet of org.apache.bcel.classfile.AnnotationEntry

    protected String dumpAnnotationEntries(final AnnotationEntry[] as)

{

final StringBuilder result = new StringBuilder();

result.append("[");

for (int i = 0; i < as.length; i++)

{

final AnnotationEntry annotation = as[i];

result.append(annotation.toShortString());

if (i + 1 < as.length) {

result.append(",");

}

}

result.append("]");

return result.toString();

}


   Like      Feedback      org.apache.bcel.classfile.AnnotationEntry


 Sample 12. Code Sample / Example / Snippet of org.apache.bcel.classfile.Deprecated

    public Attribute copy( final ConstantPool _constant_pool ) {

final Deprecated c = (Deprecated) clone();

if (bytes != null) {

c.bytes = new byte[bytes.length];

System.arraycopy(bytes, 0, c.bytes, 0, bytes.length);

}

c.setConstantPool(_constant_pool);

return c;

}


   Like      Feedback      org.apache.bcel.classfile.Deprecated


 Sample 13. Code Sample / Example / Snippet of org.apache.bcel.classfile.Field

        public void visitGETSTATIC(final GETSTATIC o) {

try {

final String field_name = o.getFieldName(cpg);

final JavaClass jc = Repository.lookupClass(getObjectType(o).getClassName());

final Field[] fields = jc.getFields();

Field f = null;

for (final Field field : fields) {

if (field.getName().equals(field_name)) {

f = field;

break;

}

}

if (f == null) {

throw new AssertionViolatedException("Field '" + field_name + "' not found in " + jc.getClassName());

}



if (! (f.isStatic())) {

constraintViolated(o, "Referenced field '"+f+"' is not static which it should be.");

}

} catch (final ClassNotFoundException e) {

throw new AssertionViolatedException("Missing class: " + e, e);

}

}




   Like      Feedback      org.apache.bcel.classfile.Field


 Sample 14. Declaring static block

public abstract class TestClass {
static{
init();
}

public static void main(String[] args){
}

private init(){
}
}

   Like      Feedback     static block  abstract class declaration


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 Sample 15. Check if an object is an instanceOf class or derived class or implementing interface

DerivedClass dc = new DerivedClass();

if (dc instanceof BaseClass) {
}

   Like      Feedback     instanceof


 Sample 16. Constant Class

public class Constants {
public static final long ZERO = 0L;
public static final long HUNDRED = 100L;
public static final long THOUSAND = 1000L;
}

   Like      Feedback     constant class  static final variable


 Sample 17. Database Api using java.sql classes

package BuggyBread;

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.SQLException;

public class DatabaseAPI {

   // JDBC driver name and database URL
   static final String JDBC_DRIVER = "com.mysql.jdbc.Driver";
   static final String DB_URL = "";

   // Database credentials
   static final String USER = "";
   static final String PASS = "";

   Connection conn = null;
   
   public void initializeConnection(){
      try {
         // STEP 2: Register JDBC driver
         Class.forName("com.mysql.jdbc.Driver");

         // STEP 3: Open a connection
         System.out.println("Connecting to database...");
         conn = DriverManager.getConnection(DB_URL, USER, PASS);

         conn.close();
      } catch (SQLException se) {
         // Handle errors for JDBC
         se.printStackTrace();
      } catch (Exception e) {
         // Handle errors for Class.forName
         e.printStackTrace();
      } finally {
         
         try {
            if (conn != null)
               conn.close();
         } catch (SQLException se) {
            se.printStackTrace();
         }// end finally try
      }// end try
   
   }
}

   Like      Feedback     database api  java.sql


 Sample 18. Load Library

System.loadLibrary("jawt");

   Like      Feedback     System Class  system  System.loadLibrary


 Sample 19. Loading Class using Class.forName ( Reflection )

Class clazz = null;
try {
   clazz = Class.forName("sun.awt.windows.WEmbeddedFrame");
} catch (Throwable e) {
}

Constructor constructor = null;
try {
   constructor = clazz.getConstructor(new Class[] { Integer.TYPE });
} catch (Throwable localThrowable1) {
}

   Like      Feedback     Class.forName  Reflection


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 Sample 20. Repeat a string using Google Guava Strings Class

System.out.println(Strings.repeat("Hello", 5));

   Like      Feedback     google guava  google guava string  strings.repeat  repeat characters   repeat string


 Sample 21. Get the properties of class (i.e package name , interfaces , subclasses etc ) using ClassUtils( Apache Commons )

Class class1 = ClassUtils.getClass("BuggyBreadTest"); 
System.out.println(ClassUtils.getPackageName(class1));
System.out.println(ClassUtils.getAllInterfaces(class1));

   Like      Feedback     ClassUtils  Apache Commons  Get Class Properties  java.lang.Class


 Sample 22. Code Sample / Example / Snippet of org.apache.spark.ml.classification.LogisticRegression

  public static void main(String[] args) {

SparkConf conf = new SparkConf().setAppName("JavaLogisticRegressionWithElasticNetExample");

JavaSparkContext jsc = new JavaSparkContext(conf);

SQLContext sqlContext = new SQLContext(jsc);



DataFrame training = sqlContext.read().format("libsvm")

.load("data/mllib/sample_libsvm_data.txt");



LogisticRegression lr = new LogisticRegression()

.setMaxIter(10)

.setRegParam(0.3)

.setElasticNetParam(0.8);



LogisticRegressionModel lrModel = lr.fit(training);



System.out.println("Coefficients: "

+ lrModel.coefficients() + " Intercept: " + lrModel.intercept());



jsc.stop();

}


   Like      Feedback      org.apache.spark.ml.classification.LogisticRegression


 Sample 23. Code Sample / Example / Snippet of org.apache.spark.mllib.classification.LogisticRegressionModel

  public static void main(String[] args) {

SparkConf conf = new SparkConf().setAppName("JavaLogisticRegressionWithElasticNetExample");

JavaSparkContext jsc = new JavaSparkContext(conf);

SQLContext sqlContext = new SQLContext(jsc);



DataFrame training = sqlContext.read().format("libsvm")

.load("data/mllib/sample_libsvm_data.txt");



LogisticRegression lr = new LogisticRegression()

.setMaxIter(10)

.setRegParam(0.3)

.setElasticNetParam(0.8);



LogisticRegressionModel lrModel = lr.fit(training);



System.out.println("Coefficients: "

+ lrModel.coefficients() + " Intercept: " + lrModel.intercept());



jsc.stop();

}


   Like      Feedback      org.apache.spark.mllib.classification.LogisticRegressionModel


 Sample 24. Code Sample / Example / Snippet of org.apache.bcel.classfile.AnnotationDefault

    public void testMethodAnnotations() throws ClassNotFoundException

{

final JavaClass clazz = getTestClass(PACKAGE_BASE_NAME+".data.SimpleAnnotation");

final Method m = getMethod(clazz, "fruit");

final AnnotationDefault a = (AnnotationDefault) findAttribute(

"AnnotationDefault", m.getAttributes());

final SimpleElementValue val = (SimpleElementValue) a.getDefaultValue();

assertTrue("Should be STRING but is " + val.getElementValueType(), val

.getElementValueType() == ElementValue.STRING);

assertTrue("Should have default of bananas but default is "

+ val.getValueString(), val.getValueString().equals("bananas"));

}


   Like      Feedback      org.apache.bcel.classfile.AnnotationDefault


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 Sample 25. Code Sample / Example / Snippet of org.apache.bcel.classfile.Method

    public void testMethodAnnotations() throws ClassNotFoundException

{

final JavaClass clazz = getTestClass(PACKAGE_BASE_NAME+".data.SimpleAnnotation");

final Method m = getMethod(clazz, "fruit");

final AnnotationDefault a = (AnnotationDefault) findAttribute(

"AnnotationDefault", m.getAttributes());

final SimpleElementValue val = (SimpleElementValue) a.getDefaultValue();

assertTrue("Should be STRING but is " + val.getElementValueType(), val

.getElementValueType() == ElementValue.STRING);

assertTrue("Should have default of bananas but default is "

+ val.getValueString(), val.getValueString().equals("bananas"));

}


   Like      Feedback      org.apache.bcel.classfile.Method


 Sample 26. Code Sample / Example / Snippet of org.apache.bcel.classfile.SimpleElementValue

    public void testMethodAnnotations() throws ClassNotFoundException

{

final JavaClass clazz = getTestClass(PACKAGE_BASE_NAME+".data.SimpleAnnotation");

final Method m = getMethod(clazz, "fruit");

final AnnotationDefault a = (AnnotationDefault) findAttribute(

"AnnotationDefault", m.getAttributes());

final SimpleElementValue val = (SimpleElementValue) a.getDefaultValue();

assertTrue("Should be STRING but is " + val.getElementValueType(), val

.getElementValueType() == ElementValue.STRING);

assertTrue("Should have default of bananas but default is "

+ val.getValueString(), val.getValueString().equals("bananas"));

}


   Like      Feedback      org.apache.bcel.classfile.SimpleElementValue


 Sample 27. Code Sample / Example / Snippet of org.apache.bcel.classfile.JavaClass

    public void testMethodAnnotations() throws ClassNotFoundException

{

final JavaClass clazz = getTestClass(PACKAGE_BASE_NAME+".data.SimpleAnnotation");

final Method m = getMethod(clazz, "fruit");

final AnnotationDefault a = (AnnotationDefault) findAttribute(

"AnnotationDefault", m.getAttributes());

final SimpleElementValue val = (SimpleElementValue) a.getDefaultValue();

assertTrue("Should be STRING but is " + val.getElementValueType(), val

.getElementValueType() == ElementValue.STRING);

assertTrue("Should have default of bananas but default is "

+ val.getValueString(), val.getValueString().equals("bananas"));

}


   Like      Feedback      org.apache.bcel.classfile.JavaClass


 Sample 28. Code Sample / Example / Snippet of org.apache.bcel.classfile.Attribute

    protected String dumpAttributes(final Attribute[] as)

{

final StringBuilder result = new StringBuilder();

result.append("AttributeArray:[");

for (int i = 0; i < as.length; i++)

{

final Attribute attr = as[i];

result.append(attr.toString());

if (i + 1 < as.length) {

result.append(",");

}

}

result.append("]");

return result.toString();

}


   Like      Feedback      org.apache.bcel.classfile.Attribute


 Sample 29. Code Sample / Example / Snippet of org.apache.bcel.generic.ClassGen

    public void testCreateIntegerElementValue() throws Exception

{

final ClassGen cg = createClassGen("HelloWorld");

final ConstantPoolGen cp = cg.getConstantPool();

final SimpleElementValueGen evg = new SimpleElementValueGen(

ElementValueGen.PRIMITIVE_INT, cp, 555);

assertTrue("Should have the same index in the constantpool but "

+ evg.getIndex() + "!=" + cp.lookupInteger(555),

evg.getIndex() == cp.lookupInteger(555));

checkSerialize(evg, cp);

}


   Like      Feedback      org.apache.bcel.generic.ClassGen


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 Sample 30. Code Sample / Example / Snippet of org.apache.bcel.generic.ClassElementValueGen

    public void testCreateClassElementValue() throws Exception

{

final ClassGen cg = createClassGen("HelloWorld");

final ConstantPoolGen cp = cg.getConstantPool();

final ObjectType classType = new ObjectType("java.lang.Integer");

final ClassElementValueGen evg = new ClassElementValueGen(classType, cp);

assertTrue("Unexpected value for contained class: '"

+ evg.getClassString() + "'", evg.getClassString().contains("Integer"));

checkSerialize(evg, cp);

}


   Like      Feedback      org.apache.bcel.generic.ClassElementValueGen


 Sample 31. Code Sample / Example / Snippet of org.apache.bcel.classfile.EnclosingMethod

    public void testCheckMethodLevelNamedInnerClass()

throws ClassNotFoundException

{

final JavaClass clazz = getTestClass(PACKAGE_BASE_NAME+".data.AttributeTestClassEM01$1S");

final ConstantPool pool = clazz.getConstantPool();

final Attribute[] encMethodAttrs = findAttribute("EnclosingMethod", clazz);

assertTrue("Expected 1 EnclosingMethod attribute but found "

+ encMethodAttrs.length, encMethodAttrs.length == 1);

final EnclosingMethod em = (EnclosingMethod) encMethodAttrs[0];

final String enclosingClassName = em.getEnclosingClass().getBytes(pool);

final String enclosingMethodName = em.getEnclosingMethod().getName(pool);

assertTrue(

"Expected class name to be '"+PACKAGE_BASE_SIG+"/data/AttributeTestClassEM01' but was "

+ enclosingClassName, enclosingClassName

.equals(PACKAGE_BASE_SIG+"/data/AttributeTestClassEM01"));

assertTrue("Expected method name to be 'main' but was "

+ enclosingMethodName, enclosingMethodName.equals("main"));

}


   Like      Feedback      org.apache.bcel.classfile.EnclosingMethod


 Sample 32. Code Sample / Example / Snippet of org.apache.bcel.classfile.ConstantPool

    public void testCheckMethodLevelNamedInnerClass()

throws ClassNotFoundException

{

final JavaClass clazz = getTestClass(PACKAGE_BASE_NAME+".data.AttributeTestClassEM01$1S");

final ConstantPool pool = clazz.getConstantPool();

final Attribute[] encMethodAttrs = findAttribute("EnclosingMethod", clazz);

assertTrue("Expected 1 EnclosingMethod attribute but found "

+ encMethodAttrs.length, encMethodAttrs.length == 1);

final EnclosingMethod em = (EnclosingMethod) encMethodAttrs[0];

final String enclosingClassName = em.getEnclosingClass().getBytes(pool);

final String enclosingMethodName = em.getEnclosingMethod().getName(pool);

assertTrue(

"Expected class name to be '"+PACKAGE_BASE_SIG+"/data/AttributeTestClassEM01' but was "

+ enclosingClassName, enclosingClassName

.equals(PACKAGE_BASE_SIG+"/data/AttributeTestClassEM01"));

assertTrue("Expected method name to be 'main' but was "

+ enclosingMethodName, enclosingMethodName.equals("main"));

}


   Like      Feedback      org.apache.bcel.classfile.ConstantPool


 Sample 33. Code Sample / Example / Snippet of org.apache.bcel.classfile.ArrayElementValue

    private void assertArrayElementValue(final int nExpectedArrayValues, final AnnotationEntry anno)

{

final ElementValuePair elementValuePair = anno.getElementValuePairs()[0];

assertEquals("value", elementValuePair.getNameString());

final ArrayElementValue ev = (ArrayElementValue) elementValuePair.getValue();

final ElementValue[] eva = ev.getElementValuesArray();

assertEquals(nExpectedArrayValues, eva.length);

}


   Like      Feedback      org.apache.bcel.classfile.ArrayElementValue


 Sample 34. Code Sample / Example / Snippet of org.apache.bcel.classfile.ElementValuePair

    private void assertArrayElementValue(final int nExpectedArrayValues, final AnnotationEntry anno)

{

final ElementValuePair elementValuePair = anno.getElementValuePairs()[0];

assertEquals("value", elementValuePair.getNameString());

final ArrayElementValue ev = (ArrayElementValue) elementValuePair.getValue();

final ElementValue[] eva = ev.getElementValuesArray();

assertEquals(nExpectedArrayValues, eva.length);

}


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 Sample 35. Code Sample / Example / Snippet of org.apache.bcel.classfile.ClassParser

    private void testJar(final File file) throws Exception {

System.out.println(file);

try (JarFile jar = new JarFile(file)) {

final Enumeration<JarEntry> en = jar.entries();

while (en.hasMoreElements()) {

final JarEntry e = en.nextElement();

final String name = e.getName();

if (name.endsWith(".class")) {

try (InputStream in = jar.getInputStream(e)) {

final ClassParser parser = new ClassParser(in, name);

final JavaClass jc = parser.parse();

for (final Method m : jc.getMethods()) {

compare(name, m);

}

}

}

}

}

}


   Like      Feedback      org.apache.bcel.classfile.ClassParser


 Sample 36. Code Sample / Example / Snippet of org.apache.bcel.classfile.Code

    private void compare(final String name, final Method m) {

final Code c = m.getCode();

if (c == null) {

return; // e.g. abstract method

}

final byte[] src = c.getCode();

final InstructionList il = new InstructionList(src);

final byte[] out = il.getByteCode();

if (src.length == out.length) {

assertArrayEquals(name + ": " + m.toString(), src, out);

} else {

System.out.println(name + ": " + m.toString() + " " + src.length + " " + out.length);

System.out.println(bytesToHex(src));

System.out.println(bytesToHex(out));

for (final InstructionHandle ih : il) {

System.out.println(ih.toString(false));

}

fail("Array comparison failure");

}

}


   Like      Feedback      org.apache.bcel.classfile.Code


 Sample 37. Code Sample / Example / Snippet of org.apache.bcel.classfile.LocalVariableTable

    public void testB79() throws ClassNotFoundException

{

final JavaClass clazz = getTestClass(PACKAGE_BASE_NAME+".data.PLSETestClass");

final ClassGen gen = new ClassGen(clazz);

final ConstantPoolGen pool = gen.getConstantPool();

final Method m = gen.getMethodAt(2);

final LocalVariableTable lvt = m.getLocalVariableTable();

final MethodGen mg = new MethodGen(m, gen.getClassName(), pool);

final LocalVariableTable new_lvt = mg.getLocalVariableTable(mg.getConstantPool());

assertEquals("number of locals", lvt.getTableLength(), new_lvt.getTableLength());

}


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 Sample 38. Code Sample / Example / Snippet of org.apache.bcel.classfile.ConstantUtf8

    public static String[] getClassDependencies(ConstantPool pool) {

String[] tempArray = new String[pool.getLength()];

int size = 0;

StringBuilder buf = new StringBuilder();



for (int idx = 0; idx < pool.getLength(); idx++) {

Constant c = pool.getConstant(idx);

if (c != null && c.getTag() == Constants.CONSTANT_Class) {

ConstantUtf8 c1 = (ConstantUtf8) pool.getConstant(((ConstantClass) c).getNameIndex());

buf.setLength(0);

buf.append(c1.getBytes());

for (int n = 0; n < buf.length(); n++) {

if (buf.charAt(n) == '/') {

buf.setCharAt(n, '.');

}

}



tempArray[size++] = buf.toString();

}

}



String[] dependencies = new String[size];

System.arraycopy(tempArray, 0, dependencies, 0, size);

return dependencies;

}


   Like      Feedback      org.apache.bcel.classfile.ConstantUtf8


 Sample 39. Code Sample / Example / Snippet of org.apache.bcel.classfile.ConstantNameAndType

    private void visitRef(ConstantCP ccp, boolean method) {

String class_name = ccp.getClass(cp);

add(class_name);



ConstantNameAndType cnat = (ConstantNameAndType) cp.getConstant(ccp.getNameAndTypeIndex(),

Constants.CONSTANT_NameAndType);



String signature = cnat.getSignature(cp);



if (method) {

Type type = Type.getReturnType(signature);



checkType(type);



for (Type type1 : Type.getArgumentTypes(signature)) {

checkType(type1);

}

} else {

checkType(Type.getType(signature));

}

}


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 Sample 40. Code Sample / Example / Snippet of org.apache.bcel.util.ClassPath

    public static ClassPath.ClassFile lookupClassFile( final String class_name ) {

try {

final ClassPath path = repository.getClassPath();

if (path == null) {

return null;

}

return path.getClassFile(class_name);

} catch (final IOException e) {

return null;

}

}


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 Sample 41. Code Sample / Example / Snippet of org.apache.bcel.classfile.Constant

    public String getEnumTypeString()

{

return ((ConstantUtf8) getConstantPool().getConstant(typeIdx))

.getBytes();

}


   Like      Feedback      org.apache.bcel.classfile.Constant


 Sample 42. Code Sample / Example / Snippet of org.apache.bcel.classfile.ConstantInteger

    public int getValueInt()

{

if (super.getElementValueType() != PRIMITIVE_INT) {

throw new RuntimeException(

"Dont call getValueString() on a non STRING ElementValue");

}

final ConstantInteger c = (ConstantInteger) getConstantPool().getConstant(idx);

return c.getBytes();

}


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 Sample 43. Code Sample / Example / Snippet of org.apache.bcel.classfile.ConstantClass

    public String getEnumTypeString()

{

return ((ConstantUtf8) getConstantPool().getConstant(typeIdx))

.getBytes();

}


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 Sample 44. Code Sample / Example / Snippet of org.apache.bcel.classfile.ConstantCP

    public String getClassName( final ConstantPoolGen cpg ) {

final ConstantPool cp = cpg.getConstantPool();

final ConstantCP cmr = (ConstantCP) cp.getConstant(super.getIndex());

final String className = cp.getConstantString(cmr.getClassIndex(), Const.CONSTANT_Class);

if (className.startsWith("[")) {

return "java.lang.Object";

}

return className.replace('/', '.');

}


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 Sample 45. Code Sample / Example / Snippet of org.apache.bcel.classfile.Annotations

    public FieldGen(final Field field, final ConstantPoolGen cp) {

this(field.getAccessFlags(), Type.getType(field.getSignature()), field.getName(), cp);

final Attribute[] attrs = field.getAttributes();

for (final Attribute attr : attrs) {

if (attr instanceof ConstantValue) {

setValue(((ConstantValue) attr).getConstantValueIndex());

} else if (attr instanceof Annotations) {

final Annotations runtimeAnnotations = (Annotations)attr;

final AnnotationEntry[] annotationEntries = runtimeAnnotations.getAnnotationEntries();

for (final AnnotationEntry element : annotationEntries) {

addAnnotationEntry(new AnnotationEntryGen(element,cp,false));

}

} else {

addAttribute(attr);

}

}

}


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 Sample 46. Code Sample / Example / Snippet of org.apache.bcel.classfile.ConstantFloat

    public int lookupFloat( final float n ) {

final int bits = Float.floatToIntBits(n);

for (int i = 1; i < index; i++) {

if (constants[i] instanceof ConstantFloat) {

final ConstantFloat c = (ConstantFloat) constants[i];

if (Float.floatToIntBits(c.getBytes()) == bits) {

return i;

}

}

}

return -1;

}


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 Sample 47. Code Sample / Example / Snippet of org.apache.bcel.classfile.ConstantString

    public String stringifyValue()

{

final ConstantUtf8 cu8 = (ConstantUtf8) getConstantPool().getConstant(valueIdx);

return cu8.getBytes();

}


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 Sample 48. Code Sample / Example / Snippet of org.apache.bcel.classfile.ConstantLong

    public int lookupLong( final long n ) {

for (int i = 1; i < index; i++) {

if (constants[i] instanceof ConstantLong) {

final ConstantLong c = (ConstantLong) constants[i];

if (c.getBytes() == n) {

return i;

}

}

}

return -1;

}


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 Sample 49. Code Sample / Example / Snippet of org.apache.bcel.classfile.ConstantDouble

    public int lookupDouble( final double n ) {

final long bits = Double.doubleToLongBits(n);

for (int i = 1; i < index; i++) {

if (constants[i] instanceof ConstantDouble) {

final ConstantDouble c = (ConstantDouble) constants[i];

if (Double.doubleToLongBits(c.getBytes()) == bits) {

return i;

}

}

}

return -1;

}


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 Sample 50. Code Sample / Example / Snippet of org.apache.bcel.classfile.ConstantValue

    public void visitField( final Field field ) {

_out.println();

_out.println(" field = new FieldGen(" + printFlags(field.getAccessFlags()) + ", "

+ printType(field.getSignature()) + ", "" + field.getName() + "", _cp);");

final ConstantValue cv = field.getConstantValue();

if (cv != null) {

final String value = cv.toString();

_out.println(" field.setInitValue(" + value + ")");

}

_out.println(" _cg.addField(field.getField());");

}


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 Sample 51. Code Sample / Example / Snippet of org.apache.bcel.util.ClassQueue

    public JavaClass[] getAllInterfaces() throws ClassNotFoundException {

final ClassQueue queue = new ClassQueue();

final Set<JavaClass> allInterfaces = new TreeSet<>();

queue.enqueue(this);

while (!queue.empty()) {

final JavaClass clazz = queue.dequeue();

final JavaClass souper = clazz.getSuperClass();

final JavaClass[] _interfaces = clazz.getInterfaces();

if (clazz.isInterface()) {

allInterfaces.add(clazz);

} else {

if (souper != null) {

queue.enqueue(souper);

}

}

for (final JavaClass _interface : _interfaces) {

queue.enqueue(_interface);

}

}

return allInterfaces.toArray(new JavaClass[allInterfaces.size()]);

}


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 Sample 52. Code Sample / Example / Snippet of org.apache.bcel.classfile.MethodParameters

    public Attribute copy(final ConstantPool _constant_pool) {

final MethodParameters c = (MethodParameters) clone();

c.parameters = new MethodParameter[parameters.length];



for (int i = 0; i < parameters.length; i++) {

c.parameters[i] = parameters[i].copy();

}

c.setConstantPool(_constant_pool);

return c;

}


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 Sample 53. Code Sample / Example / Snippet of org.apache.bcel.classfile.BootstrapMethods

    public BootstrapMethods copy(final ConstantPool _constant_pool) {

final BootstrapMethods c = (BootstrapMethods) clone();

c.bootstrap_methods = new BootstrapMethod[bootstrap_methods.length];



for (int i = 0; i < bootstrap_methods.length; i++) {

c.bootstrap_methods[i] = bootstrap_methods[i].copy();

}

c.setConstantPool(_constant_pool);

return c;

}


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 Sample 54. Code Sample / Example / Snippet of org.apache.bcel.classfile.InnerClasses

public Attribute copy(final ConstantPool _constant_pool) {
final InnerClasses c = (InnerClasses) clone();
c.inner_classes = new InnerClass[inner_classes.length];
for (int i = 0; i < inner_classes.length; i++) {
c.inner_classes[i] = inner_classes[i].copy();
}
c.setConstantPool(_constant_pool);
return c;
}

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 Sample 55. Code Sample / Example / Snippet of org.apache.bcel.classfile.Synthetic

    public Attribute copy( final ConstantPool _constant_pool ) {

final Synthetic c = (Synthetic) clone();

if (bytes != null) {

c.bytes = new byte[bytes.length];

System.arraycopy(bytes, 0, c.bytes, 0, bytes.length);

}

c.setConstantPool(_constant_pool);

return c;

}


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 Sample 56. Code Sample / Example / Snippet of org.apache.bcel.classfile.LocalVariableTypeTable

    public Attribute copy(final ConstantPool constant_pool) {

final LocalVariableTypeTable c = (LocalVariableTypeTable) clone();



c.local_variable_type_table = new LocalVariable[local_variable_type_table.length];

for (int i = 0; i < local_variable_type_table.length; i++) {

c.local_variable_type_table[i] = local_variable_type_table[i].copy();

}



c.setConstantPool(constant_pool);

return c;

}


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 Sample 57. Code Sample / Example / Snippet of org.apache.bcel.classfile.Node

  public void jjtAddChild(Node n, int i) {

if (children == null) {

children = new Node[i + 1];

} else if (i >= children.length) {

Node c[] = new Node[i + 1];

System.arraycopy(children, 0, c, 0, children.length);

children = c;

}

children[i] = n;

}


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 Sample 58. Code Sample / Example / Snippet of org.apache.bcel.classfile.ParameterAnnotations

  public static ParameterAnnotationEntry[] createParameterAnnotationEntries(final Attribute[] attrs) {

final List<ParameterAnnotationEntry> accumulatedAnnotations = new ArrayList<>(attrs.length);

for (final Attribute attribute : attrs) {

if (attribute instanceof ParameterAnnotations) {

final ParameterAnnotations runtimeAnnotations = (ParameterAnnotations)attribute;

Collections.addAll(accumulatedAnnotations, runtimeAnnotations.getParameterAnnotationEntries());

}

}

return accumulatedAnnotations.toArray(new ParameterAnnotationEntry[accumulatedAnnotations.size()]);

}


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 Sample 59. Code Sample / Example / Snippet of org.apache.bcel.classfile.Unknown

    public Attribute copy( final ConstantPool _constant_pool ) {

final Unknown c = (Unknown) clone();

if (bytes != null) {

c.bytes = new byte[bytes.length];

System.arraycopy(bytes, 0, c.bytes, 0, bytes.length);

}

c.setConstantPool(_constant_pool);

return c;

}


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 Sample 60. Code Sample / Example / Snippet of org.apache.bcel.classfile.StackMap

    public Attribute copy( final ConstantPool _constant_pool ) {

final StackMap c = (StackMap) clone();

c.map = new StackMapEntry[map.length];

for (int i = 0; i < map.length; i++) {

c.map[i] = map[i].copy();

}

c.setConstantPool(_constant_pool);

return c;

}


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 Sample 61. Code Sample / Example / Snippet of org.apache.bcel.classfile.LineNumberTable

    public Attribute copy( final ConstantPool _constant_pool ) {

final LineNumberTable c = (LineNumberTable) clone();

c.line_number_table = new LineNumber[line_number_table.length];

for (int i = 0; i < line_number_table.length; i++) {

c.line_number_table[i] = line_number_table[i].copy();

}

c.setConstantPool(_constant_pool);

return c;

}


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 Sample 62. Code Sample / Example / Snippet of org.apache.bcel.classfile.DescendingVisitor

    private void field_and_method_refs_are_valid() {

try {

final JavaClass jc = Repository.lookupClass(myOwner.getClassName());

final DescendingVisitor v = new DescendingVisitor(jc, new FAMRAV_Visitor(jc));

v.visit();



} catch (final ClassNotFoundException e) {

throw new AssertionViolatedException("Missing class: " + e, e);

}

}


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 Sample 63. Usage of Builder Class / Builder Pattern

public class BuggyBread {

   private String element1; // Make them private as it supports stronger encapsulation

   private String element2;

   private BuggyBread(String element1, String element2){ // Make it private so that it can only be used by Builder
      this.element1 = element1;
      this.element2 = element2;
   }

   public static class Builder {
      // Create Builder as nested class as its only supposed to Build BuggyBread objects,
      // Make it public so that it can be accessed from outside
      private String element1; // Make them private as it supports stronger encapsulation

      private String element2;

      Builder(){}; // We have to define this constructor if we need overloaded constructor too and need to initialize without arguments too

      Builder(BuggyBread buggybread){ // overloaded constructor to make things easy
         element1 = buggybread.element1;
         element2 = buggybread.element2;
      }

      Builder withElement1(String element1){ // Builder method to either populate elements or override ( if populated through overloaded constructor )
         this.element1 = element1;
         return this;
      }

      Builder withElement2(String element2){
         this.element2 = element2;
         return this;
      }

      BuggyBread build(){ // method to build BuggyBread object using final contents from Builder
         BuggyBread buggybread = new BuggyBread(element1,element2);
         return buggybread;
      }
   }
}

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 Sample 64. Write a Program to show Java thread usage by extending Thread class

public class MyClass {
   static class MyThreadClass extends Thread{

      @Override
      public void run() {
         System.out.println("Hello");
         try {
            Thread.sleep(1000);
            System.out.println("Hello Again");
         } catch (InterruptedException e) {
            e.printStackTrace();
         }
         
      }
      
   }
   
   public static void main(String[] args){
      MyThreadClass myThreadClass = new MyThreadClass();
      myThreadClass.start();
      
      MyThreadClass myThreadClass2 = new MyThreadClass();
      myThreadClass2.start();
   }
}

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 Sample 65. Code to get Module name for the class

Module module = Test.class.getModule();
System.out.println(module.getName());

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 Sample 66. Code to get Module name for List class

Module module = java.util.List.class.getModule();
System.out.println(module.getName()); // prints java.base

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 Sample 67. Code to get main class in a particular module

Module module = java.util.List.class.getModule();
ModuleDescriptor moduleDescriptor = module.getDescriptor();
System.out.println(moduleDescriptor.mainClass());

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