add wallet table to store layout settings

src/main/java/com/sparrowwallet/drongo/wallet/TableType.java

@@ -0,0 +1,5 @@
+package com.sparrowwallet.drongo.wallet;
+
+public enum TableType {
+    TRANSACTIONS, UTXOS, RECEIVE_ADDRESSES, CHANGE_ADDRESSES, SEARCH_WALLET, WALLET_SUMMARY
+}

src/main/java/com/sparrowwallet/drongo/wallet/Wallet.java

@@ -41,6 +41,7 @@ public class Wallet extends Persistable implements Comparable<Wallet> {
     private final Map<Sha256Hash, BlockTransaction> transactions = new HashMap<>();
     private final Map<String, String> detachedLabels = new HashMap<>();
     private WalletConfig walletConfig;
+    private final Map<TableType, WalletTable> walletTables = new HashMap<>();
     private MixConfig mixConfig;
     private final Map<Sha256Hash, UtxoMixData> utxoMixes = new HashMap<>();
     private Integer storedBlockHeight;
@@ -466,6 +467,14 @@ public class Wallet extends Persistable implements Comparable<Wallet> {
         this.walletConfig = walletConfig;
     }
 
+    public Map<TableType, WalletTable> getWalletTables() {
+        return walletTables;
+    }
+
+    public WalletTable getWalletTable(TableType tableType) {
+        return walletTables.get(tableType);
+    }
+
     public MixConfig getMixConfig() {
         return mixConfig;
     }

src/main/java/com/sparrowwallet/drongo/wallet/WalletTable.java

@@ -0,0 +1,36 @@
+package com.sparrowwallet.drongo.wallet;
+
+public class WalletTable extends Persistable {
+    private final TableType tableType;
+    private final Double[] widths;
+
+    public WalletTable(TableType tableType, Double[] widths) {
+        this.tableType = tableType;
+        this.widths = widths;
+    }
+
+    public TableType getTableType() {
+        return tableType;
+    }
+
+    public Double[] getWidths() {
+        return widths;
+    }
+
+    @Override
+    public final boolean equals(Object o) {
+        if(this == o) {
+            return true;
+        }
+        if(!(o instanceof WalletTable that)) {
+            return false;
+        }
+
+        return tableType == that.tableType;
+    }
+
+    @Override
+    public int hashCode() {
+        return tableType.hashCode();
+    }
+}