fix: resolve some sonar warnings

jadx-core/src/main/java/jadx/core/codegen/ClassGen.java

@@ -298,12 +298,10 @@ public class ClassGen {
 		} else {
 			insertDecompilationProblems(code, mth);
 			boolean badCode = mth.contains(AFlag.INCONSISTENT_CODE);
-			if (badCode) {
-				if (showInconsistentCode) {
-					code.startLine("/* Code decompiled incorrectly, please refer to instructions dump. */");
-					mth.remove(AFlag.INCONSISTENT_CODE);
-					badCode = false;
-				}
+			if (badCode && showInconsistentCode) {
+				code.startLine("/* Code decompiled incorrectly, please refer to instructions dump. */");
+				mth.remove(AFlag.INCONSISTENT_CODE);
+				badCode = false;
 			}
 			MethodGen mthGen;
 			if (badCode || mth.contains(AType.JADX_ERROR) || fallback) {

jadx-core/src/main/java/jadx/core/codegen/InsnGen.java

@@ -224,7 +224,7 @@ public class InsnGen {
 					code.add(';');
 				}
 			}
-		} catch (Throwable th) {
+		} catch (Exception th) {
 			throw new CodegenException(mth, "Error generate insn: " + insn, th);
 		}
 		return true;

jadx-core/src/main/java/jadx/core/codegen/NameGen.java

@@ -7,7 +7,6 @@ import java.util.Set;
 
 import jadx.core.Consts;
 import jadx.core.deobf.NameMapper;
-import jadx.core.dex.attributes.AFlag;
 import jadx.core.dex.attributes.nodes.LoopLabelAttr;
 import jadx.core.dex.info.ClassInfo;
 import jadx.core.dex.info.MethodInfo;

jadx-core/src/main/java/jadx/core/dex/attributes/AType.java

@@ -53,4 +53,7 @@ public class AType<T extends IAttribute> {
 	public static final AType<DeclareVariablesAttr> DECLARE_VARIABLES = new AType<>();
 	public static final AType<LoopLabelAttr> LOOP_LABEL = new AType<>();
 	public static final AType<IgnoreEdgeAttr> IGNORE_EDGE = new AType<>();
+
+	private AType() {
+	}
 }

jadx-core/src/main/java/jadx/core/dex/instructions/InsnDecoder.java

@@ -2,9 +2,7 @@ package jadx.core.dex.instructions;
 
 import java.io.EOFException;
 
-import com.android.dex.ClassData;
 import com.android.dex.Code;
-import com.android.dex.FieldId;
 import com.android.dx.io.OpcodeInfo;
 import com.android.dx.io.Opcodes;
 import com.android.dx.io.instructions.DecodedInstruction;
@@ -12,9 +10,6 @@ import com.android.dx.io.instructions.FillArrayDataPayloadDecodedInstruction;
 import com.android.dx.io.instructions.PackedSwitchPayloadDecodedInstruction;
 import com.android.dx.io.instructions.ShortArrayCodeInput;
 import com.android.dx.io.instructions.SparseSwitchPayloadDecodedInstruction;
-import jadx.core.dex.info.ClassInfo;
-import jadx.core.dex.nodes.ClassNode;
-import jadx.core.dex.nodes.FieldNode;
 import org.jetbrains.annotations.NotNull;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
@@ -117,17 +112,15 @@ public class InsnDecoder {
 						InsnArg.lit(insn, ArgType.WIDE));
 
 			case Opcodes.CONST_STRING:
-			case Opcodes.CONST_STRING_JUMBO: {
-				InsnNode node = new ConstStringNode(dex.getString(insn.getIndex()));
-				node.setResult(InsnArg.reg(insn, 0, ArgType.STRING));
-				return node;
-			}
+			case Opcodes.CONST_STRING_JUMBO:
+				InsnNode constStrInsn = new ConstStringNode(dex.getString(insn.getIndex()));
+				constStrInsn.setResult(InsnArg.reg(insn, 0, ArgType.STRING));
+				return constStrInsn;
 
-			case Opcodes.CONST_CLASS: {
-				InsnNode node = new ConstClassNode(dex.getType(insn.getIndex()));
-				node.setResult(InsnArg.reg(insn, 0, ArgType.CLASS));
-				return node;
-			}
+			case Opcodes.CONST_CLASS:
+				InsnNode constClsInsn = new ConstClassNode(dex.getType(insn.getIndex()));
+				constClsInsn.setResult(InsnArg.reg(insn, 0, ArgType.CLASS));
+				return constClsInsn;
 
 			case Opcodes.MOVE:
 			case Opcodes.MOVE_16:
@@ -427,20 +420,18 @@ public class InsnDecoder {
 						null,
 						InsnArg.reg(insn, 0, method.getReturnType()));
 
-			case Opcodes.INSTANCE_OF: {
-				InsnNode node = new IndexInsnNode(InsnType.INSTANCE_OF, dex.getType(insn.getIndex()), 1);
-				node.setResult(InsnArg.reg(insn, 0, ArgType.BOOLEAN));
-				node.addArg(InsnArg.reg(insn, 1, ArgType.UNKNOWN_OBJECT));
-				return node;
-			}
+			case Opcodes.INSTANCE_OF:
+				InsnNode instInsn = new IndexInsnNode(InsnType.INSTANCE_OF, dex.getType(insn.getIndex()), 1);
+				instInsn.setResult(InsnArg.reg(insn, 0, ArgType.BOOLEAN));
+				instInsn.addArg(InsnArg.reg(insn, 1, ArgType.UNKNOWN_OBJECT));
+				return instInsn;
 
-			case Opcodes.CHECK_CAST: {
+			case Opcodes.CHECK_CAST:
 				ArgType castType = dex.getType(insn.getIndex());
-				InsnNode node = new IndexInsnNode(InsnType.CHECK_CAST, castType, 1);
-				node.setResult(InsnArg.reg(insn, 0, castType));
-				node.addArg(InsnArg.reg(insn, 0, ArgType.UNKNOWN_OBJECT));
-				return node;
-			}
+				InsnNode checkCastInsn = new IndexInsnNode(InsnType.CHECK_CAST, castType, 1);
+				checkCastInsn.setResult(InsnArg.reg(insn, 0, castType));
+				checkCastInsn.addArg(InsnArg.reg(insn, 0, ArgType.UNKNOWN_OBJECT));
+				return checkCastInsn;
 
 			case Opcodes.IGET:
 			case Opcodes.IGET_BOOLEAN:
@@ -448,13 +439,12 @@ public class InsnDecoder {
 			case Opcodes.IGET_CHAR:
 			case Opcodes.IGET_SHORT:
 			case Opcodes.IGET_WIDE:
-			case Opcodes.IGET_OBJECT: {
-				FieldInfo field = FieldInfo.fromDex(dex, insn.getIndex());
-				InsnNode node = new IndexInsnNode(InsnType.IGET, field, 1);
-				node.setResult(InsnArg.reg(insn, 0, field.getType()));
-				node.addArg(InsnArg.reg(insn, 1, field.getDeclClass().getType()));
-				return node;
-			}
+			case Opcodes.IGET_OBJECT:
+				FieldInfo igetFld = FieldInfo.fromDex(dex, insn.getIndex());
+				InsnNode igetInsn = new IndexInsnNode(InsnType.IGET, igetFld, 1);
+				igetInsn.setResult(InsnArg.reg(insn, 0, igetFld.getType()));
+				igetInsn.addArg(InsnArg.reg(insn, 1, igetFld.getDeclClass().getType()));
+				return igetInsn;
 
 			case Opcodes.IPUT:
 			case Opcodes.IPUT_BOOLEAN:
@@ -462,13 +452,12 @@ public class InsnDecoder {
 			case Opcodes.IPUT_CHAR:
 			case Opcodes.IPUT_SHORT:
 			case Opcodes.IPUT_WIDE:
-			case Opcodes.IPUT_OBJECT: {
-				FieldInfo field = FieldInfo.fromDex(dex, insn.getIndex());
-				InsnNode node = new IndexInsnNode(InsnType.IPUT, field, 2);
-				node.addArg(InsnArg.reg(insn, 0, field.getType()));
-				node.addArg(InsnArg.reg(insn, 1, field.getDeclClass().getType()));
-				return node;
-			}
+			case Opcodes.IPUT_OBJECT:
+				FieldInfo iputFld = FieldInfo.fromDex(dex, insn.getIndex());
+				InsnNode iputInsn = new IndexInsnNode(InsnType.IPUT, iputFld, 2);
+				iputInsn.addArg(InsnArg.reg(insn, 0, iputFld.getType()));
+				iputInsn.addArg(InsnArg.reg(insn, 1, iputFld.getDeclClass().getType()));
+				return iputInsn;
 
 			case Opcodes.SGET:
 			case Opcodes.SGET_BOOLEAN:
@@ -476,12 +465,11 @@ public class InsnDecoder {
 			case Opcodes.SGET_CHAR:
 			case Opcodes.SGET_SHORT:
 			case Opcodes.SGET_WIDE:
-			case Opcodes.SGET_OBJECT: {
-				FieldInfo field = FieldInfo.fromDex(dex, insn.getIndex());
-				InsnNode node = new IndexInsnNode(InsnType.SGET, field, 0);
-				node.setResult(InsnArg.reg(insn, 0, field.getType()));
-				return node;
-			}
+			case Opcodes.SGET_OBJECT:
+				FieldInfo sgetFld = FieldInfo.fromDex(dex, insn.getIndex());
+				InsnNode sgetInsn = new IndexInsnNode(InsnType.SGET, sgetFld, 0);
+				sgetInsn.setResult(InsnArg.reg(insn, 0, sgetFld.getType()));
+				return sgetInsn;
 
 			case Opcodes.SPUT:
 			case Opcodes.SPUT_BOOLEAN:
@@ -489,19 +477,17 @@ public class InsnDecoder {
 			case Opcodes.SPUT_CHAR:
 			case Opcodes.SPUT_SHORT:
 			case Opcodes.SPUT_WIDE:
-			case Opcodes.SPUT_OBJECT: {
-				FieldInfo field = FieldInfo.fromDex(dex, insn.getIndex());
-				InsnNode node = new IndexInsnNode(InsnType.SPUT, field, 1);
-				node.addArg(InsnArg.reg(insn, 0, field.getType()));
-				return node;
-			}
-
-			case Opcodes.ARRAY_LENGTH: {
-				InsnNode node = new InsnNode(InsnType.ARRAY_LENGTH, 1);
-				node.setResult(InsnArg.reg(insn, 0, ArgType.INT));
-				node.addArg(InsnArg.reg(insn, 1, ArgType.array(ArgType.UNKNOWN)));
-				return node;
-			}
+			case Opcodes.SPUT_OBJECT:
+				FieldInfo sputFld = FieldInfo.fromDex(dex, insn.getIndex());
+				InsnNode sputInsn = new IndexInsnNode(InsnType.SPUT, sputFld, 1);
+				sputInsn.addArg(InsnArg.reg(insn, 0, sputFld.getType()));
+				return sputInsn;
+
+			case Opcodes.ARRAY_LENGTH:
+				InsnNode arrLenInsn = new InsnNode(InsnType.ARRAY_LENGTH, 1);
+				arrLenInsn.setResult(InsnArg.reg(insn, 0, ArgType.INT));
+				arrLenInsn.addArg(InsnArg.reg(insn, 1, ArgType.array(ArgType.UNKNOWN)));
+				return arrLenInsn;
 
 			case Opcodes.AGET:
 				return arrayGet(insn, ArgType.NARROW);

jadx-core/src/main/java/jadx/core/dex/nodes/ClassNode.java

@@ -15,7 +15,6 @@ import com.android.dex.ClassDef;
 import com.android.dex.Dex;
 import com.android.dx.rop.code.AccessFlags;
 import org.jetbrains.annotations.Nullable;
-import org.jetbrains.annotations.TestOnly;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 

jadx-core/src/main/java/jadx/core/dex/nodes/RootNode.java

 package jadx.core.dex.nodes;
 
-import java.io.IOException;
-import java.io.InputStream;
 import java.util.ArrayList;
 import java.util.List;
 
-import com.android.dex.Dex;
-import jadx.core.dex.info.FieldInfo;
 import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
 import org.slf4j.Logger;
@@ -19,6 +15,7 @@ import jadx.api.ResourcesLoader;
 import jadx.core.clsp.ClspGraph;
 import jadx.core.dex.info.ClassInfo;
 import jadx.core.dex.info.ConstStorage;
+import jadx.core.dex.info.FieldInfo;
 import jadx.core.dex.info.InfoStorage;
 import jadx.core.dex.info.MethodInfo;
 import jadx.core.utils.ErrorsCounter;
@@ -28,7 +25,6 @@ import jadx.core.utils.exceptions.JadxException;
 import jadx.core.utils.exceptions.JadxRuntimeException;
 import jadx.core.utils.files.DexFile;
 import jadx.core.utils.files.InputFile;
-import jadx.core.xmlgen.ResContainer;
 import jadx.core.xmlgen.ResTableParser;
 import jadx.core.xmlgen.ResourceStorage;
 

jadx-core/src/main/java/jadx/core/dex/visitors/EnumVisitor.java

@@ -3,6 +3,8 @@ package jadx.core.dex.visitors;
 import java.util.ArrayList;
 import java.util.List;
 
+import org.jetbrains.annotations.Nullable;
+
 import jadx.core.codegen.TypeGen;
 import jadx.core.deobf.NameMapper;
 import jadx.core.dex.attributes.AFlag;
@@ -27,7 +29,6 @@ import jadx.core.dex.nodes.MethodNode;
 import jadx.core.utils.ErrorsCounter;
 import jadx.core.utils.InsnUtils;
 import jadx.core.utils.exceptions.JadxException;
-import org.jetbrains.annotations.Nullable;
 
 @JadxVisitor(
 		name = "EnumVisitor",

jadx-core/src/main/java/jadx/core/dex/visitors/regions/CheckRegions.java

@@ -45,14 +45,12 @@ public class CheckRegions extends AbstractVisitor {
 				if (blocksInRegions.add(block)) {
 					return;
 				}
-				if (!block.contains(AFlag.RETURN)
+				if (LOG.isDebugEnabled()
+						&& !block.contains(AFlag.RETURN)
 						&& !block.contains(AFlag.SKIP)
 						&& !block.contains(AFlag.SYNTHETIC)
 						&& !block.getInstructions().isEmpty()) {
-					if (LOG.isDebugEnabled()) {
-						LOG.debug("Duplicated block: {} - {}", mth, block);
-					}
-					//mth.addWarn("Duplicated block: " + block);
+					LOG.debug("Duplicated block: {} - {}", mth, block);
 				}
 			}
 		});
@@ -90,7 +88,8 @@ public class CheckRegions extends AbstractVisitor {
 		for (InsnNode insn : block.getInstructions()) {
 			try {
 				ig.makeInsn(insn, code);
-			} catch (CodegenException ignored) {
+			} catch (CodegenException e) {
+				// ignore
 			}
 		}
 		code.newLine().addIndent();

jadx-core/src/main/java/jadx/core/utils/Utils.java

@@ -91,19 +91,26 @@ public class Utils {
 			@Override
 			public void write(int b) {
 				char c = (char) b;
-				if (c == '\r') {
-					// ignore
-				} else if (c == '\n') {
-					code.startLine();
-				} else {
-					code.add(c);
+				switch (c) {
+					case '\n':
+						code.startLine();
+						break;
+
+					case '\r':
+						// ignore
+						break;
+
+					default:
+						code.add(c);
+						break;
 				}
 			}
 		};
-		PrintWriter pw = new PrintWriter(w, true);
-		filterRecursive(throwable);
-		throwable.printStackTrace(pw);
-		pw.flush();
+		try (PrintWriter pw = new PrintWriter(w, true)) {
+			filterRecursive(throwable);
+			throwable.printStackTrace(pw);
+			pw.flush();
+		}
 	}
 
 	private static void filterRecursive(Throwable th) {

jadx-gui/src/main/java/jadx/gui/JadxGUI.java

@@ -2,20 +2,15 @@ package jadx.gui;
 
 import javax.swing.*;
 
-import jadx.gui.utils.LangLocale;
-import jadx.gui.utils.NLS;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
 import jadx.gui.settings.JadxSettings;
 import jadx.gui.settings.JadxSettingsAdapter;
 import jadx.gui.ui.MainWindow;
+import jadx.gui.utils.NLS;
 import jadx.gui.utils.logs.LogCollector;
 
-import java.util.Locale;
-import java.util.prefs.BackingStoreException;
-import java.util.prefs.Preferences;
-
 public class JadxGUI {
 	private static final Logger LOG = LoggerFactory.getLogger(JadxGUI.class);
 

jadx-gui/src/main/java/jadx/gui/settings/JadxSettingsAdapter.java

 package jadx.gui.settings;
 
 import java.lang.reflect.Modifier;
-import java.lang.reflect.Type;
 import java.util.prefs.Preferences;
 
 import com.google.gson.ExclusionStrategy;

jadx-gui/src/main/java/jadx/gui/treemodel/JCertificate.java

 package jadx.gui.treemodel;
+
+import javax.swing.*;
+import java.io.BufferedInputStream;
+import java.io.File;
+import java.io.FileInputStream;
+import java.io.IOException;
+import java.io.InputStream;
+import java.util.zip.ZipEntry;
+import java.util.zip.ZipFile;
+
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
 import jadx.api.ResourceFile;
 import jadx.core.utils.files.ZipSecurity;
 import jadx.gui.utils.CertificateManager;
 import jadx.gui.utils.NLS;
 import jadx.gui.utils.Utils;
-import javax.swing.*;
-import java.io.*;
-import java.util.zip.ZipEntry;
-import java.util.zip.ZipFile;
 
 public class JCertificate extends JNode {
+	private static final long serialVersionUID = 4308696770188518731L;
 
+	private static final Logger LOG = LoggerFactory.getLogger(JCertificate.class);
 	private static final ImageIcon CERTIFICATE_ICON = Utils.openIcon("certificate_obj");
-    private final transient ResourceFile rf;
+
+	private final transient ResourceFile rf;
 
 	public JCertificate(ResourceFile resFile) {
-        this.rf = resFile;
+		this.rf = resFile;
 	}
 
 	@Override
@@ -35,7 +47,6 @@ public class JCertificate extends JNode {
 
 	@Override
 	public String getContent() {
-
 		try {
 			ResourceFile.ZipRef zipRef = rf.getZipRef();
 			if (zipRef == null) {
@@ -53,17 +64,13 @@ public class JCertificate extends JNode {
 						return null;
 					}
 					try (InputStream inputStream = new BufferedInputStream(zipFile.getInputStream(entry))) {
-						return  CertificateManager.decode(inputStream);
+						return CertificateManager.decode(inputStream);
 					}
 				}
 			}
 		} catch (Exception e) {
-			e.printStackTrace();
-		//	throw new JadxException("Error decode: " + rf.getName(), e);
+			LOG.error("Certificate decode error: {}", rf.getName(), e);
+			return "Decode error: " + e.getMessage();
 		}
-
-		return null;
 	}
-
-
 }

jadx-gui/src/main/java/jadx/gui/ui/CertificatePanel.java

 package jadx.gui.ui;
 
-import jadx.gui.treemodel.JNode;
-
 import javax.swing.*;
 import java.awt.*;
 
+import jadx.gui.treemodel.JNode;
+
 public class CertificatePanel extends ContentPanel {
     CertificatePanel(TabbedPane panel, JNode jnode) {
         super(panel, jnode);

jadx-gui/src/main/java/jadx/gui/ui/MainWindow.java

@@ -28,7 +28,6 @@ import java.util.Arrays;
 import java.util.Timer;
 import java.util.TimerTask;
 
-import jadx.gui.treemodel.*;
 import org.fife.ui.rsyntaxtextarea.Theme;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
@@ -40,6 +39,12 @@ import jadx.gui.jobs.DecompileJob;
 import jadx.gui.jobs.IndexJob;
 import jadx.gui.settings.JadxSettings;
 import jadx.gui.settings.JadxSettingsWindow;
+import jadx.gui.treemodel.JCertificate;
+import jadx.gui.treemodel.JClass;
+import jadx.gui.treemodel.JLoadableNode;
+import jadx.gui.treemodel.JNode;
+import jadx.gui.treemodel.JResource;
+import jadx.gui.treemodel.JRoot;
 import jadx.gui.update.JadxUpdate;
 import jadx.gui.update.JadxUpdate.IUpdateCallback;
 import jadx.gui.update.data.Release;

jadx-gui/src/main/java/jadx/gui/ui/TabbedPane.java

 package jadx.gui.ui;
 
-import org.jetbrains.annotations.Nullable;
-import org.slf4j.Logger;
-import org.slf4j.LoggerFactory;
-
-import java.awt.Component;
-import java.awt.FlowLayout;
-import java.awt.event.ActionEvent;
-import java.awt.event.ActionListener;
+import javax.swing.*;
+import javax.swing.plaf.basic.BasicButtonUI;
+import javax.swing.text.BadLocationException;
+import java.awt.*;
 import java.awt.event.MouseAdapter;
 import java.awt.event.MouseEvent;
-import java.awt.event.MouseWheelEvent;
-import java.awt.event.MouseWheelListener;
 import java.util.ArrayList;
 import java.util.LinkedHashMap;
 import java.util.List;
 import java.util.Map;
 
-import javax.swing.BorderFactory;
-import javax.swing.ImageIcon;
-import javax.swing.JButton;
-import javax.swing.JLabel;
-import javax.swing.JMenuItem;
-import javax.swing.JPanel;
-import javax.swing.JPopupMenu;
-import javax.swing.JTabbedPane;
-import javax.swing.SwingUtilities;
-import javax.swing.plaf.basic.BasicButtonUI;
-import javax.swing.text.BadLocationException;
+import org.jetbrains.annotations.Nullable;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
 
 import jadx.api.ResourceFile;
 import jadx.api.ResourceType;
@@ -57,19 +43,17 @@ class TabbedPane extends JTabbedPane {
 
 		setTabLayoutPolicy(JTabbedPane.SCROLL_TAB_LAYOUT);
 
-		addMouseWheelListener(new MouseWheelListener() {
-			public void mouseWheelMoved(MouseWheelEvent e) {
-				int direction = e.getWheelRotation();
-				int index = getSelectedIndex();
-				int maxIndex = getTabCount() - 1;
-				if ((index == 0 && direction < 0)
-						|| (index == maxIndex && direction > 0)) {
-					index = maxIndex - index;
-				} else {
-					index += direction;
-				}
-				setSelectedIndex(index);
+		addMouseWheelListener(e -> {
+			int direction = e.getWheelRotation();
+			int index = getSelectedIndex();
+			int maxIndex = getTabCount() - 1;
+			if ((index == 0 && direction < 0)
+					|| (index == maxIndex && direction > 0)) {
+				index = maxIndex - index;
+			} else {
+				index += direction;
 			}
+			setSelectedIndex(index);
 		});
 	}
 
@@ -82,23 +66,20 @@ class TabbedPane extends JTabbedPane {
 		if (contentPanel == null) {
 			return;
 		}
-		SwingUtilities.invokeLater(new Runnable() {
-			@Override
-			public void run() {
-				setSelectedComponent(contentPanel);
-				CodeArea codeArea = contentPanel.getCodeArea();
-				int line = pos.getLine();
-				if (line < 0) {
-					try {
-						line = 1 + codeArea.getLineOfOffset(-line);
-					} catch (BadLocationException e) {
-						LOG.error("Can't get line for: {}", pos, e);
-						line = pos.getNode().getLine();
-					}
+		SwingUtilities.invokeLater(() -> {
+			setSelectedComponent(contentPanel);
+			CodeArea codeArea = contentPanel.getCodeArea();
+			int line = pos.getLine();
+			if (line < 0) {
+				try {
+					line = 1 + codeArea.getLineOfOffset(-line);
+				} catch (BadLocationException e) {
+					LOG.error("Can't get line for: {}", pos, e);
+					line = pos.getNode().getLine();
 				}
-				codeArea.scrollToLine(line);
-				codeArea.requestFocus();
 			}
+			codeArea.scrollToLine(line);
+			codeArea.requestFocus();
 		});
 	}
 
@@ -107,12 +88,7 @@ class TabbedPane extends JTabbedPane {
 		if (contentPanel == null) {
 			return;
 		}
-		SwingUtilities.invokeLater(new Runnable() {
-			@Override
-			public void run() {
-				setSelectedComponent(contentPanel);
-			}
-		});
+		SwingUtilities.invokeLater(() -> setSelectedComponent(contentPanel));
 	}
 
 	public void showCertificate(JCertificate cert) {
@@ -120,15 +96,9 @@ class TabbedPane extends JTabbedPane {
 		if (contentPanel == null) {
 			return;
 		}
-		SwingUtilities.invokeLater(new Runnable() {
-			@Override
-			public void run() {
-				setSelectedComponent(contentPanel);
-			}
-		});
+		SwingUtilities.invokeLater(() -> setSelectedComponent(contentPanel));
 	}
 
-
 	public void codeJump(Position pos) {
 		Position curPos = getCurrentPosition();
 		if (curPos != null) {
@@ -198,11 +168,9 @@ class TabbedPane extends JTabbedPane {
 				return null;
 			}
 		}
-		if(node instanceof JCertificate)
-		{
-			return new CertificatePanel(this,node);
+		if (node instanceof JCertificate) {
+			return new CertificatePanel(this, node);
 		}
-
 		return new CodePanel(this, node);
 	}
 
@@ -232,12 +200,7 @@ class TabbedPane extends JTabbedPane {
 		button.setFocusable(false);
 		button.setBorder(null);
 		button.setBorderPainted(false);
-		button.addActionListener(new ActionListener() {
-			@Override
-			public void actionPerformed(ActionEvent e) {
-				closeCodePanel(contentPanel);
-			}
-		});
+		button.addActionListener(e -> closeCodePanel(contentPanel));
 
 		panel.addMouseListener(new MouseAdapter() {
 			@Override
@@ -248,7 +211,6 @@ class TabbedPane extends JTabbedPane {
 					JPopupMenu menu = createTabPopupMenu(contentPanel);
 					menu.show(panel, e.getX(), e.getY());
 				} else {
-					// TODO: make correct event delegation to tabbed pane
 					setSelectedComponent(contentPanel);
 				}
 			}
@@ -264,45 +226,27 @@ class TabbedPane extends JTabbedPane {
 		JPopupMenu menu = new JPopupMenu();
 
 		JMenuItem copyRootClassName = new JMenuItem(NLS.str("tabs.copy_class_name"));
-		copyRootClassName.addActionListener(new ActionListener() {
-			@Override
-			public void actionPerformed(ActionEvent actionEvent) {
-				copyRootClassName();
-			}
-		});
+		copyRootClassName.addActionListener(actionEvent -> copyRootClassName());
 		menu.add(copyRootClassName);
 
 		JMenuItem closeTab = new JMenuItem(NLS.str("tabs.close"));
-		closeTab.addActionListener(new ActionListener() {
-			@Override
-			public void actionPerformed(ActionEvent e) {
-				closeCodePanel(contentPanel);
-			}
-		});
+		closeTab.addActionListener(e -> closeCodePanel(contentPanel));
 		menu.add(closeTab);
 
 		if (openTabs.size() > 1) {
 			JMenuItem closeOther = new JMenuItem(NLS.str("tabs.closeOthers"));
-			closeOther.addActionListener(new ActionListener() {
-				@Override
-				public void actionPerformed(ActionEvent e) {
-					List<ContentPanel> contentPanels = new ArrayList<>(openTabs.values());
-					for (ContentPanel panel : contentPanels) {
-						if (panel != contentPanel) {
-							closeCodePanel(panel);
-						}
+			closeOther.addActionListener(e -> {
+				List<ContentPanel> contentPanels = new ArrayList<>(openTabs.values());
+				for (ContentPanel panel : contentPanels) {
+					if (panel != contentPanel) {
+						closeCodePanel(panel);
 					}
 				}
 			});
 			menu.add(closeOther);
 
 			JMenuItem closeAll = new JMenuItem(NLS.str("tabs.closeAll"));
-			closeAll.addActionListener(new ActionListener() {
-				@Override
-				public void actionPerformed(ActionEvent e) {
-					closeAllTabs();
-				}
-			});
+			closeAll.addActionListener(e -> closeAllTabs());
 			menu.add(closeAll);
 			menu.addSeparator();
 
@@ -315,12 +259,7 @@ class TabbedPane extends JTabbedPane {
 				JNode node = entry.getKey();
 				final String clsName = node.makeLongString();
 				JMenuItem item = new JMenuItem(clsName);
-				item.addActionListener(new ActionListener() {
-					@Override
-					public void actionPerformed(ActionEvent e) {
-						setSelectedComponent(cp);
-					}
-				});
+				item.addActionListener(e -> setSelectedComponent(cp));
 				item.setIcon(node.getIcon());
 				menu.add(item);
 			}
@@ -335,13 +274,15 @@ class TabbedPane extends JTabbedPane {
 		}
 	}
 
-	public void copyRootClassName(){
+	public void copyRootClassName() {
 		ContentPanel selectedPanel = getSelectedCodePanel();
-		JNode node = selectedPanel.getNode();
-		JClass jClass = node.getRootClass();
-		if (jClass != null){
-			String name = jClass.getFullName();
-			Utils.setClipboardString(name);
+		if (selectedPanel != null) {
+			JNode node = selectedPanel.getNode();
+			JClass jClass = node.getRootClass();
+			if (jClass != null) {
+				String name = jClass.getFullName();
+				Utils.setClipboardString(name);
+			}
 		}
 	}
 

jadx-gui/src/main/java/jadx/gui/utils/CertificateManager.java

 package jadx.gui.utils;
+
 import java.io.InputStream;
 import java.security.MessageDigest;
 import java.security.NoSuchAlgorithmException;
@@ -11,112 +12,95 @@ import java.security.cert.X509Certificate;
 import java.security.interfaces.DSAPublicKey;
 import java.security.interfaces.RSAPublicKey;
 import java.util.Collection;
+import java.util.Collections;
+
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
 
 public class CertificateManager {
+	private static final Logger LOG = LoggerFactory.getLogger(CertificateManager.class);
+	private static final String CERTIFICATE_TYPE_NAME = "X.509";
+
+	private X509Certificate x509cert;
+	private Certificate cert;
 
-	static public String decode(InputStream in){
+	public static String decode(InputStream in) {
 		StringBuilder strBuild = new StringBuilder();
 		Collection<? extends Certificate> certificates = readCertificates(in);
-		if(certificates!=null) {
+		if (certificates != null) {
 			for (Certificate cert : certificates) {
-				CertificateManager certificateManager= new CertificateManager(cert);
+				CertificateManager certificateManager = new CertificateManager(cert);
 				strBuild.append(certificateManager.generateText());
 			}
 		}
 		return strBuild.toString();
 	}
 
-
-	 static Collection<? extends Certificate> readCertificates(InputStream in) {
-		CertificateFactory cf;
+	static Collection<? extends Certificate> readCertificates(InputStream in) {
 		try {
-			cf = CertificateFactory.getInstance("X.509");
-			Collection<? extends Certificate> certs = cf.generateCertificates(in);
-			in.close();
-			return certs;
+			CertificateFactory cf = CertificateFactory.getInstance(CERTIFICATE_TYPE_NAME);
+			return cf.generateCertificates(in);
 		} catch (Exception e) {
-			e.printStackTrace();
+			LOG.error("Certificate read error", e);
 		}
-		return null;
+		return Collections.emptyList();
 	}
 
-
-	private X509Certificate x509cert;
-	private Certificate cert;
-
-	public  CertificateManager(Certificate cert)
-	{
+	public CertificateManager(Certificate cert) {
 		this.cert = cert;
 		String type = cert.getType();
-		if (type.equals("X.509")) {
-			if (cert instanceof X509Certificate) {
-				x509cert = (X509Certificate) cert;
-			}
+		if (type.equals(CERTIFICATE_TYPE_NAME) && cert instanceof X509Certificate) {
+			x509cert = (X509Certificate) cert;
 		}
 	}
 
-
-	String generateHeader()
-	{
+	String generateHeader() {
 		StringBuilder builder = new StringBuilder();
 		append(builder, NLS.str("certificate.cert_type"), x509cert.getType());
-		append(builder, NLS.str("certificate.serialSigVer"),((Integer) x509cert.getVersion()).toString());
-		// seral number
+		append(builder, NLS.str("certificate.serialSigVer"), ((Integer) x509cert.getVersion()).toString());
+		// serial number
 		append(builder, NLS.str("certificate.serialNumber"), "0x" + x509cert.getSerialNumber().toString(16));
 
 		// Get subject
 		Principal subjectDN = x509cert.getSubjectDN();
 		append(builder, NLS.str("certificate.cert_subject"), subjectDN.getName());
 
-		// Get issuer
-//		Principal issuerDN = x509cert.getIssuerDN();
-//		append(str, NLS.str("certificate.cert_issuer"), issuerDN.getName());
-
 		append(builder, NLS.str("certificate.serialValidFrom"), x509cert.getNotBefore().toString());
 		append(builder, NLS.str("certificate.serialValidUntil"), x509cert.getNotAfter().toString());
-		return  builder.toString();
-
+		return builder.toString();
 	}
 
-	String generateSignature()
-	{
+	String generateSignature() {
 		StringBuilder builder = new StringBuilder();
 		append(builder, NLS.str("certificate.serialSigType"), x509cert.getSigAlgName());
 		append(builder, NLS.str("certificate.serialSigOID"), x509cert.getSigAlgOID());
-		return  builder.toString();
+		return builder.toString();
 	}
 
-	String generateFingerprint()
-	{
+	String generateFingerprint() {
 		StringBuilder builder = new StringBuilder();
 		try {
 			append(builder, NLS.str("certificate.serialMD5"), getThumbPrint(x509cert, "MD5"));
 			append(builder, NLS.str("certificate.serialSHA1"), getThumbPrint(x509cert, "SHA-1"));
 			append(builder, NLS.str("certificate.serialSHA256"), getThumbPrint(x509cert, "SHA-256"));
-
-		} catch (NoSuchAlgorithmException e) {
-			e.printStackTrace();
-		} catch (CertificateEncodingException e) {
-			e.printStackTrace();
+		} catch (Exception e) {
+			LOG.error("Failed to parse fingerprint", e);
 		}
-		return  builder.toString();
+		return builder.toString();
 	}
 
-	String generatePublicKey()
-	{
+	String generatePublicKey() {
 		PublicKey publicKey = x509cert.getPublicKey();
-		if(publicKey instanceof RSAPublicKey)
-		{
+		if (publicKey instanceof RSAPublicKey) {
 			return generateRSAPublicKey();
 		}
-		if(publicKey instanceof DSAPublicKey)
-		{
+		if (publicKey instanceof DSAPublicKey) {
 			return generateDSAPublicKey();
 		}
 		return "";
 	}
-	String generateRSAPublicKey()
-	{
+
+	String generateRSAPublicKey() {
 		RSAPublicKey pub = (RSAPublicKey) cert.getPublicKey();
 		StringBuilder builder = new StringBuilder();
 
@@ -127,21 +111,18 @@ public class CertificateManager {
 		return builder.toString();
 	}
 
-	String generateDSAPublicKey()
-	{
+	String generateDSAPublicKey() {
 		DSAPublicKey pub = (DSAPublicKey) cert.getPublicKey();
 		StringBuilder builder = new StringBuilder();
 		append(builder, NLS.str("certificate.serialPubKeyType"), pub.getAlgorithm());
 		append(builder, NLS.str("certificate.serialPubKeyY"), pub.getY().toString(10));
 
 		return builder.toString();
-
 	}
 
-	String generateTextForX509()
-	{
+	String generateTextForX509() {
 		StringBuilder builder = new StringBuilder();
-		if(x509cert!=null){
+		if (x509cert != null) {
 			builder.append(generateHeader());
 			builder.append("\n");
 
@@ -151,31 +132,23 @@ public class CertificateManager {
 			builder.append(generateSignature());
 			builder.append("\n");
 			builder.append(generateFingerprint());
-
 		}
-
 		return builder.toString();
-
-
 	}
 
-
-
-	 private String generateText() {
+	private String generateText() {
 		StringBuilder str = new StringBuilder();
 		String type = cert.getType();
-		if (!type.equals("X.509")) {
-			str.append(cert.toString());
-		} else {
+		if (type.equals(CERTIFICATE_TYPE_NAME)) {
 			str.append(generateTextForX509());
+		} else {
+			str.append(cert.toString());
 		}
 		return str.toString();
 	}
 
-
-
 	static void append(StringBuilder str, String name, String value) {
-		str.append(name + ": " + value + "\n");
+		str.append(name).append(": ").append(value).append("\n");
 	}
 
 	public static String getThumbPrint(X509Certificate cert, String type)
@@ -185,23 +158,16 @@ public class CertificateManager {
 		md.update(der);
 		byte[] digest = md.digest();
 		return hexify(digest);
-
 	}
 
-	public static String hexify(byte bytes[]) {
-
-		char[] hexDigits = {'0', '1', '2', '3', '4', '5', '6', '7', '8', '9',
-				'A', 'B', 'C', 'D', 'E', 'F'};
-
+	public static String hexify(byte[] bytes) {
+		char[] hexDigits = {'0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'A', 'B', 'C', 'D', 'E', 'F'};
 		StringBuilder buf = new StringBuilder(bytes.length * 3);
-
-		for (int i = 0; i < bytes.length; ++i) {
-			buf.append(hexDigits[(bytes[i] & 0xf0) >> 4]);
-			buf.append(hexDigits[bytes[i] & 0x0f]);
+		for (byte aByte : bytes) {
+			buf.append(hexDigits[(aByte & 0xf0) >> 4]);
+			buf.append(hexDigits[aByte & 0x0f]);
 			buf.append(' ');
 		}
-
 		return buf.toString();
 	}
-
 }

jadx-gui/src/main/java/jadx/gui/utils/Utils.java

 package jadx.gui.utils;
 
-import org.jetbrains.annotations.Nullable;
-import org.slf4j.Logger;
-import org.slf4j.LoggerFactory;
-
-import java.awt.Font;
-import java.awt.Toolkit;
+import javax.swing.*;
+import java.awt.*;
 import java.awt.datatransfer.Clipboard;
 import java.awt.datatransfer.StringSelection;
 import java.awt.datatransfer.Transferable;
 import java.io.InputStream;
 import java.net.URL;
 
-import javax.swing.Action;
-import javax.swing.Icon;
-import javax.swing.ImageIcon;
-import javax.swing.JComponent;
-import javax.swing.KeyStroke;
+import org.jetbrains.annotations.Nullable;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
 
 import jadx.core.dex.info.AccessInfo;
 import jadx.core.dex.instructions.args.ArgType;